B.ALKANOIC ACIDS (Carboxylic acids) (A) INTRODUCTION. Alkanoic acids belong to a homologous series of organic compounds with a general formula CnH2n +1 COOH and thus -COOH as the functional group .The 1st ten alkanoic acids include:
78 Alkanoic acids like alkanols /alkanes/alkenes/alkynes form a homologous series where: (i)the general name of an alkanoic acids is derived from the alkane name then ending with “–oic” acid as the table above shows. (ii) the members have R-COOH/R C-O-H as the functional group. n General /molecular formular Structural formula IUPAC name 0 HCOOH H – C –O - H │ O Methanoic acid 1 CH3 COOH H H – C – C – O - H │ H O Ethanoic acid 2 CH3 CH2 COOH C2 H5 COOH H H H-C – C – C – O – H H H O Propanoic acid 3 CH3 CH2 CH2 COOH C3 H7 COOH H H H H- C - C – C – C – O – H H H H O Butanoic acid 4 CH3CH2CH2CH2 COOH C4 H9 COOH H H H H H - C – C - C – C – C – O – H H H H H O Pentanoic acid 5 CH3CH2 CH2CH2CH2 COOH C5 H11 COOH H H H H H H C - C – C - C – C – C – O – H H H H H H O Hexanoic acid 6 CH3CH2 CH2 CH2CH2CH2 COOH C6 H13 COOH H H H H H H H C C - C – C - C – C – C – O – H H H H H H H O Pentanoic acid
79 O (iii)they have the same general formula represented by R-COOH where R is an alkyl group. (iv)each member differ by –CH2- group from the next/previous. (v)they show a similar and gradual change in their physical properties e.g. boiling and melting point. (vi)they show similar and gradual change in their chemical properties.


(v)they show a similar and gradual change in their physical properties e.g. boiling and melting point. (vi)they show similar and gradual change in their chemical properties. (vii) since they are acids they show similar properties with mineral acids. (B) ISOMERS OF ALKANOIC ACIDS. Alkanoic acids exhibit both structural and position isomerism. The isomers are named by using the following basic guidelines (i)Like alkanes. identify the longest carbon chain to be the parent name. (ii)Identify the position of the -C-O-H functional group to give it the smallest O /lowest position. (iii)Identify the type and position of the side group branches. Practice examples on isomers of alkanoic acids 1.Isomers of butanoic acid C3H7COOH CH3 CH2 CH2 COOH Butan-1-oic acid CH3 H2C C COOH 2-methylpropan-1-oic acid 2-methylpropan-1-oic acid and Butan-1-oic acid are structural isomers because the position of the functional group does not change but the arrangement of the atoms in the molecule does. 2.Isomers of pentanoic acid C4H9COOH CH3CH2CH2CH2 COOH pentan-1-oic acid CH3 CH3CH2CH COOH 2-methylbutan-1-oic acid
80 CH3 H3C C COOH 2,2-dimethylpropan-1-oic acid CH3 3.Ethan-1,2-dioic acid O O HOOC- COOH // H - O – C - C – O – H 4.Propan-1,3-dioic acid O H O HOOC- CH2COOH // H - O – C – C - C – O – H H 5.Butan-1,4-dioic acid O H H O HOOC CH2 CH2 COOH H- O – C – C - C – C –O – H H H 6.2,2-dichloroethan-1,2-dioic acid HOOCCHCl2 Cl H – O - C – C – Cl O H (C) LABORATORY AND INDUSTRIAL PREPARATIONOF ALKANOIC ACIDS.


(iii)Identify the type and position of the side group branches. Practice examples on isomers of alkanoic acids 1.Isomers of butanoic acid C3H7COOH CH3 CH2 CH2 COOH Butan-1-oic acid CH3 H2C C COOH 2-methylpropan-1-oic acid 2-methylpropan-1-oic acid and Butan-1-oic acid are structural isomers because the position of the functional group does not change but the arrangement of the atoms in the molecule does. 2.Isomers of pentanoic acid C4H9COOH CH3CH2CH2CH2 COOH pentan-1-oic acid CH3 CH3CH2CH COOH 2-methylbutan-1-oic acid
80 CH3 H3C C COOH 2,2-dimethylpropan-1-oic acid CH3 3.Ethan-1,2-dioic acid O O HOOC- COOH // H - O – C - C – O – H 4.Propan-1,3-dioic acid O H O HOOC- CH2COOH // H - O – C – C - C – O – H H 5.Butan-1,4-dioic acid O H H O HOOC CH2 CH2 COOH H- O – C – C - C – C –O – H H H 6.2,2-dichloroethan-1,2-dioic acid HOOCCHCl2 Cl H – O - C – C – Cl O H (C) LABORATORY AND INDUSTRIAL PREPARATIONOF ALKANOIC ACIDS. In a school laboratory, alkanoic acids can be prepared by adding an oxidizing agent (H+/KMnO4 or H+/K2Cr2O7)to the corresponding alkanol then warming. 81 The oxidation converts the alkanol first to an alkanal the alkanoic acid.


2.Isomers of pentanoic acid C4H9COOH CH3CH2CH2CH2 COOH pentan-1-oic acid CH3 CH3CH2CH COOH 2-methylbutan-1-oic acid
80 CH3 H3C C COOH 2,2-dimethylpropan-1-oic acid CH3 3.Ethan-1,2-dioic acid O O HOOC- COOH // H - O – C - C – O – H 4.Propan-1,3-dioic acid O H O HOOC- CH2COOH // H - O – C – C - C – O – H H 5.Butan-1,4-dioic acid O H H O HOOC CH2 CH2 COOH H- O – C – C - C – C –O – H H H 6.2,2-dichloroethan-1,2-dioic acid HOOCCHCl2 Cl H – O - C – C – Cl O H (C) LABORATORY AND INDUSTRIAL PREPARATIONOF ALKANOIC ACIDS. In a school laboratory, alkanoic acids can be prepared by adding an oxidizing agent (H+/KMnO4 or H+/K2Cr2O7)to the corresponding alkanol then warming. 81 The oxidation converts the alkanol first to an alkanal the alkanoic acid. NB Acidified KMnO4 is a stronger oxidizing agent than acidified K2Cr2O7 General equation: R- CH2 – OH + [O] --H+/KMnO4--> R- CH –O + H2O(l) (alkanol) (alkanal) R- CH – O + [O] --H+/KMnO4--> R- C –OOH (alkanal) (alkanoic acid) Examples 1.Ethanol on warming in acidified KMnO4 is oxidized to ethanal then ethanoic acid .


In a school laboratory, alkanoic acids can be prepared by adding an oxidizing agent (H+/KMnO4 or H+/K2Cr2O7)to the corresponding alkanol then warming. 81 The oxidation converts the alkanol first to an alkanal the alkanoic acid. NB Acidified KMnO4 is a stronger oxidizing agent than acidified K2Cr2O7 General equation: R- CH2 – OH + [O] --H+/KMnO4--> R- CH –O + H2O(l) (alkanol) (alkanal) R- CH – O + [O] --H+/KMnO4--> R- C –OOH (alkanal) (alkanoic acid) Examples 1.Ethanol on warming in acidified KMnO4 is oxidized to ethanal then ethanoic acid . CH3- CH2 – OH + [O] --H+/KMnO4--> CH3- CH –O + H2O(l) (ethanol) (ethanal) CH3- CH – O + [O] --H+/KMnO4--> CH3- C –OOH (ethanal) (ethanoic acid) 2Propanol on warming in acidified KMnO4 is oxidized to propanal then propanoic acid CH3- CH2 CH2 – OH + [O] --H+/KMnO4--> CH3- CH2 CH –O + H2O(l) (propanol) (propanal) CH3- CH – O + [O] --H+/KMnO4--> CH3- C –OOH (propanal) (propanoic acid) Industrially,large scale manufacture of alkanoic acid like ethanoic acid is obtained from: (a)Alkenes reacting with steam at high temperatures and pressure in presence of phosphoric(V)acid catalyst and undergo hydrolysis to form alkanols. i.e. Alkenes + Steam/water -- H2PO4 Catalyst--> Alkanol The alkanol is then oxidized by air at 5 atmosphere pressure with Manganese (II)sulphate(VI) catalyst to form the alkanoic acid.


CH3- CH2 – OH + [O] --H+/KMnO4--> CH3- CH –O + H2O(l) (ethanol) (ethanal) CH3- CH – O + [O] --H+/KMnO4--> CH3- C –OOH (ethanal) (ethanoic acid) 2Propanol on warming in acidified KMnO4 is oxidized to propanal then propanoic acid CH3- CH2 CH2 – OH + [O] --H+/KMnO4--> CH3- CH2 CH –O + H2O(l) (propanol) (propanal) CH3- CH – O + [O] --H+/KMnO4--> CH3- C –OOH (propanal) (propanoic acid) Industrially,large scale manufacture of alkanoic acid like ethanoic acid is obtained from: (a)Alkenes reacting with steam at high temperatures and pressure in presence of phosphoric(V)acid catalyst and undergo hydrolysis to form alkanols. i.e. Alkenes + Steam/water -- H2PO4 Catalyst--> Alkanol The alkanol is then oxidized by air at 5 atmosphere pressure with Manganese (II)sulphate(VI) catalyst to form the alkanoic acid. Alkanol + Air -- MnSO4 Catalyst/5 atm pressure--> Alkanoic acid Example Ethene is mixed with steam over a phosphoric(V)acid catalyst,300oC temperature and 60 atmosphere pressure to form ethanol. 82 CH2=CH2 + H2O -> CH3 CH2OH (Ethene) (Ethanol) This is the industrial large scale method of manufacturing ethanol Ethanol is then oxidized by air at 5 atmosphere pressure with Manganese (II)sulphate(VI) catalyst to form the ethanoic acid. CH3 CH2OH + [O] -- MnSO4 Catalyst/5 atm pressure--> CH3 COOH (Ethanol) (Ethanoic acid) (b)Alkynes react with liquid water at high temperatures and pressure in presence of Mercury(II)sulphate(VI)catalyst and 30% concentrated sulphuric(VI)acid to form alkanals.


Alkanol + Air -- MnSO4 Catalyst/5 atm pressure--> Alkanoic acid Example Ethene is mixed with steam over a phosphoric(V)acid catalyst,300oC temperature and 60 atmosphere pressure to form ethanol. 82 CH2=CH2 + H2O -> CH3 CH2OH (Ethene) (Ethanol) This is the industrial large scale method of manufacturing ethanol Ethanol is then oxidized by air at 5 atmosphere pressure with Manganese (II)sulphate(VI) catalyst to form the ethanoic acid. CH3 CH2OH + [O] -- MnSO4 Catalyst/5 atm pressure--> CH3 COOH (Ethanol) (Ethanoic acid) (b)Alkynes react with liquid water at high temperatures and pressure in presence of Mercury(II)sulphate(VI)catalyst and 30% concentrated sulphuric(VI)acid to form alkanals. Alkyne + Water -- Mercury(II)sulphate(VI)catalyst--> Alkanal The alkanal is then oxidized by air at 5 atmosphere pressure with Manganese (II) sulphate(VI) catalyst to form the alkanoic acid. Alkanal + air/oxygen -- Manganese(II)sulphate(VI)catalyst--> Alkanoic acid Example Ethyne react with liquid water at high temperature and pressure with Mercury (II) sulphate (VI)catalyst and 30% concentrated sulphuric(VI)acid to form ethanal. CH = CH + H2O --HgSO4--> CH3 CH2O (Ethyne) (Ethanal) This is another industrial large scale method of manufacturing ethanol from large quantities of ethyne found in natural gas. Ethanal is then oxidized by air at 5 atmosphere pressure with Manganese (II)sulphate(VI) catalyst to form the ethanoic acid. CH3 CH2O + [O] -- MnSO4 Catalyst/5 atm pressure--> CH3 COOH (Ethanal) (Oxygen from air) (Ethanoic acid) (D) PHYSICAL AND CHEMICAL PROPERTIES OF ALKANOIC ACIDS.


CH = CH + H2O --HgSO4--> CH3 CH2O (Ethyne) (Ethanal) This is another industrial large scale method of manufacturing ethanol from large quantities of ethyne found in natural gas. Ethanal is then oxidized by air at 5 atmosphere pressure with Manganese (II)sulphate(VI) catalyst to form the ethanoic acid. CH3 CH2O + [O] -- MnSO4 Catalyst/5 atm pressure--> CH3 COOH (Ethanal) (Oxygen from air) (Ethanoic acid) (D) PHYSICAL AND CHEMICAL PROPERTIES OF ALKANOIC ACIDS. I.Physical properties of alkanoic acids
83 The table below shows some physical properties of alkanoic acids Alkanol Melting point(oC) Boiling point(oC) Density(gcm-3) Solubility in water Methanoic acid 18.4 101 1.22 soluble Ethanoic acid 16.6 118 1.05 soluble Propanoic acid -2.8 141 0.992 soluble Butanoic acid -8.0 164 0.964 soluble Pentanoic acid -9.0 187 0.939 Slightly soluble Hexanoic acid -11 205 0.927 Slightly soluble Heptanoic acid -3 223 0.920 Slightly soluble Octanoic acid 11 239 0.910 Slightly soluble Nonanoic acid 16 253 0.907 Slightly soluble Decanoic acid 31 269 0.905 Slightly soluble From the table note the following: (i) Melting and boiling point decrease as the carbon chain increases due to increase in intermolecular forces of attraction between the molecules requiring more energy to separate the molecules. (ii) The density decreases as the carbon chain increases as the intermolecular forces of attraction increases between the molecules making the molecule very close reducing their volume in unit mass. (iii) Solubility decreases as the carbon chain increases as the soluble –COOH end is shielded by increasing insoluble alkyl/hydrocarbon chain. (iv) Like alkanols ,alkanoic acids exist as dimmers due to the hydrogen bonds within the molecule. i.e..


(iii) Solubility decreases as the carbon chain increases as the soluble –COOH end is shielded by increasing insoluble alkyl/hydrocarbon chain. (iv) Like alkanols ,alkanoic acids exist as dimmers due to the hydrogen bonds within the molecule. i.e.. 84 jgthungu@gmail.com104Hydrogen bondscovalent bondsR1C O δ-…….….…H δ+O δO δH δ+……..….O δCR2R1 and 2 are extensions of the molecule.For ethanoic acid the extension is made up of CH3 – to make the structure; jgthungu@gmail.com105For ethanoic acid the extension is made up of CH3 – to make the structure;Hydrogen bondscovalent bonds CH3CO δ-…………… H δ+O δO δH δ+…………O δCCH3Ethanoic acid has a higher melting/boiling point than ethanol .This is because ethanoic acid has two/more hydrogen bond than ethanol. II Chemical properties of alkanoic acids The following experiments shows the main chemical properties of ethanoic (alkanoic) acid. (a)Effect on litmus papers Experiment Dip both blue and red litmus papers in ethanoic acid. Repeat with a solution of succinic acid, citric acid, oxalic acid, tartaric acid and dilute nitric(V)acid. Sample observations Solution/acid Observations/effect on litmus papers Inference Ethanoic acid Blue litmus paper turn red Red litmus paper remain red H3O+/H+(aq)ion
85 Succinic acid Blue litmus paper turn red Red litmus paper remain red H3O+/H+(aq)ion Citric acid Blue litmus paper turn red Red litmus paper remain red H3O+/H+(aq)ion Oxalic acid Blue litmus paper turn red Red litmus paper remain red H3O+/H+(aq)ion Tartaric acid Blue litmus paper turn red Red litmus paper remain red H3O+/H+(aq)ion Nitric(V)acid Blue litmus paper turn red Red litmus paper remain red H3O+/H+(aq)ion Explanation All acidic solutions contains H+/H3O+(aq) ions.


(a)Effect on litmus papers Experiment Dip both blue and red litmus papers in ethanoic acid. Repeat with a solution of succinic acid, citric acid, oxalic acid, tartaric acid and dilute nitric(V)acid. Sample observations Solution/acid Observations/effect on litmus papers Inference Ethanoic acid Blue litmus paper turn red Red litmus paper remain red H3O+/H+(aq)ion
85 Succinic acid Blue litmus paper turn red Red litmus paper remain red H3O+/H+(aq)ion Citric acid Blue litmus paper turn red Red litmus paper remain red H3O+/H+(aq)ion Oxalic acid Blue litmus paper turn red Red litmus paper remain red H3O+/H+(aq)ion Tartaric acid Blue litmus paper turn red Red litmus paper remain red H3O+/H+(aq)ion Nitric(V)acid Blue litmus paper turn red Red litmus paper remain red H3O+/H+(aq)ion Explanation All acidic solutions contains H+/H3O+(aq) ions. The H+ /H3O+ (aq) ions is responsible for turning blue litmus paper/solution to red (b)pH Experiment Place 2cm3 of ethaoic acid in a test tube. Add 2 drops of universal indicator solution and determine its pH. Repeat with a solution of succinic acid, citric acid, oxalic acid, tartaric acid and dilute sulphuric (VI)acid. Sample observations Solution/acid pH Inference Ethanoic acid 4/5/6 Weakly acidic Succinic acid 4/5/6 Weakly acidic Citric acid 4/5/6 Weakly acidic Oxalic acid 4/5/6 Weakly acidic Tartaric acid 4/5/6 Weakly acidic Sulphuric(VI)acid 1/2/3 Strongly acidic Explanations Alkanoic acids are weak acids that partially/partly dissociate to release few H+ ions in solution. The pH of their solution is thus 4/5/6 showing they form weakly acidic solutions when dissolved in water.


Repeat with a solution of succinic acid, citric acid, oxalic acid, tartaric acid and dilute sulphuric (VI)acid. Sample observations Solution/acid pH Inference Ethanoic acid 4/5/6 Weakly acidic Succinic acid 4/5/6 Weakly acidic Citric acid 4/5/6 Weakly acidic Oxalic acid 4/5/6 Weakly acidic Tartaric acid 4/5/6 Weakly acidic Sulphuric(VI)acid 1/2/3 Strongly acidic Explanations Alkanoic acids are weak acids that partially/partly dissociate to release few H+ ions in solution. The pH of their solution is thus 4/5/6 showing they form weakly acidic solutions when dissolved in water. All alkanoic acid dissociate to releases the “H” at the functional group in -COOH to form the alkanoate ion; –COO- Mineral acids(Sulphuric(VI)acid, Nitric(V)acid and Hydrochloric acid) are strong acids that wholly/fully dissociate to release many H+ ions in solution. The pH of their solution is thus 1/2/3 showing they form strongly acidic solutions when dissolved in water.i.e Examples 1. CH3COOH(aq) CH3COO-(aq) + H+(aq)
86 (ethanoic acid) (ethanoate ion) (few H+ ion) 2. CH3 CH2COOH(aq) CH3 CH2COO-(aq) + H+(aq) (propanoic acid) (propanoate ion) (few H+ ion) 3. CH3 CH2 CH2COOH(aq) CH3 CH2 CH2COO-(aq) + H+(aq) (Butanoic acid) (butanoate ion) (few H+ ion) 4. HOOH(aq) HOO-(aq) + H+(aq) (methanoic acid) (methanoate ion) (few H+ ion) 5. H2 SO4 (aq) SO42- (aq) + 2H+(aq) (sulphuric(VI) acid) (sulphate(VI) ion) (many H+ ion) 6.


Put about 1cm length of polished magnesium ribbon. Test any gas produced using a burning splint. Repeat with a solution of succinic acid, citric acid, oxalic acid, tartaric acid and dilute sulphuric (VI) acid. Sample observations Solution/acid Observations Inference Ethanoic acid (i)effervescence, fizzing, bubbles (ii)colourless gas produced that burn with “pop” sound/explosion H3O+/H+(aq)ion Succinic acid (i)effervescence, fizzing, bubbles (ii)colourless gas produced that burn with “pop” sound/explosion H3O+/H+(aq)ion Citric acid (i)effervescence, fizzing, bubbles (ii)colourless gas produced that burn with “pop” sound/explosion H3O+/H+(aq)ion Oxalic acid (i)effervescence, fizzing, bubbles (ii)colourless gas produced that burn with “pop” sound/explosion H3O+/H+(aq)ion Tartaric acid (i)effervescence, fizzing, bubbles (ii)colourless gas produced that burn with “pop” sound/explosion H3O+/H+(aq)ion
87 Nitric(V)acid (i)effervescence, fizzing, bubbles (ii)colourless gas produced that burn with “pop” sound/explosion H3O+/H+(aq)ion Explanation Metals higher in the reactivity series displace the hydrogen in all acids to evolve/produce hydrogen gas and form a salt. Alkanoic acids react with metals with metals to form alkanoates salt and produce/evolve hydrogen gas .Hydrogen extinguishes a burning splint with a pop sound/explosion. Only the “H”in the functional group -COOH is /are displaced and not in the alkyl hydrocarbon chain. Alkanoic acid + Metal -> Alkanoate + Hydrogen gas. i.e. Examples 1.


Alkanoic acid + Metal -> Alkanoate + Hydrogen gas. i.e. Examples 1. For a monovalent metal with monobasic acid 2R – COOH + 2M -> 2R- COOM + 2H2(g) 2.For a divalent metal with monobasic acid 2R – COOH + M -> (R- COO) 2M + H2(g) 3.For a divalent metal with dibasic acid HOOC-R-COOH+ M -> MOOC-R-COOM + H2(g) 4.For a monovalent metal with dibasic acid HOOC-R-COOH+ 2M -> MOOC-R-COOM + H2(g) 5 For mineral acids (i)Sulphuric(VI)acid is a dibasic acid H2 SO4 (aq) + 2M -> M2 SO4 (aq) + H2(g) H2 SO4 (aq) + M -> MSO4 (aq) + H2(g) (ii)Nitric(V) and hydrochloric acid are monobasic acid HNO3 (aq) + 2M -> 2MNO3 (aq) + H2(g) HNO3 (aq) + M -> M(NO3 ) 2 (aq) + H2(g) Examples 1.Sodium reacts with ethanoic acid to form sodium ethanoate and produce. hydrogen gas. Caution: This reaction is explosive. CH3COOH (aq) + Na(s) -> CH3COONa (aq) + H2(g) (Ethanoic acid) (Sodium ethanoate) 2.Calcium reacts with ethanoic acid to form calcium ethanoate and produce. hydrogen gas. 2CH3COOH (aq) + Ca(s) -> (CH3COO) 2Ca (aq) + H2(g)
88 (Ethanoic acid) (Calcium ethanoate) 3.Sodium reacts with ethan-1,2-dioic acid to form sodium ethan-1,2-dioate and produce. hydrogen gas.


hydrogen gas. 2CH3COOH (aq) + Ca(s) -> (CH3COO) 2Ca (aq) + H2(g)
88 (Ethanoic acid) (Calcium ethanoate) 3.Sodium reacts with ethan-1,2-dioic acid to form sodium ethan-1,2-dioate and produce. hydrogen gas. HOOC-COOH+ 2Na -> NaOOC - COONa + H2(g) (ethan-1,2-dioic acid) (sodium ethan-1,2-dioate) Commercial name of ethan-1,2-dioic acid is oxalic acid. The salt is sodium oxalate. 4.Magnesium reacts with ethan-1,2-dioic acid to form magnesium ethan-1,2-dioate and produce. hydrogen gas. HOOC-R-COOH+ Mg -> ( OOC - COO) Mg + H2(g) (ethan-1,2-dioic acid) (magnesium ethan-1,2-dioate) 5.Magnesium reacts with (i)Sulphuric(VI)acid to form Magnesium sulphate(VI) H2 SO4 (aq) + Mg -> MgSO4 (aq) + H2(g) (ii)Nitric(V) and hydrochloric acid are monobasic acid 2HNO3 (aq) + Mg -> M(NO3 ) 2 (aq) + H2(g) (d)Reaction with hydrogen carbonates and carbonates Experiment Place about 3cm3 of ethanoic acid in a test tube. Add about 0.5g/ ½ spatula end full of sodium hydrogen carbonate/sodium carbonate. Test the gas produced using lime water. Repeat with a solution of succinic acid, citric acid, oxalic acid, tartaric acid and dilute sulphuric (VI) acid.


Add about 0.5g/ ½ spatula end full of sodium hydrogen carbonate/sodium carbonate. Test the gas produced using lime water. Repeat with a solution of succinic acid, citric acid, oxalic acid, tartaric acid and dilute sulphuric (VI) acid. Sample observations Solution/acid Observations Inference Ethanoic acid (i)effervescence, fizzing, bubbles (ii)colourless gas produced that forms a white precipitate with lime water H3O+/H+(aq)ion Succinic acid (i)effervescence, fizzing, bubbles (ii)colourless gas produced that forms a white precipitate with lime water H3O+/H+(aq)ion Citric acid (i)effervescence, fizzing, bubbles (ii)colourless gas produced that forms a white precipitate with lime water H3O+/H+(aq)ion Oxalic acid (i)effervescence, fizzing, bubbles H3O+/H+(aq)ion
89 (ii)colourless gas produced that forms a white precipitate with lime water Tartaric acid (i)effervescence, fizzing, bubbles (ii)colourless gas produced that forms a white precipitate with lime water H3O+/H+(aq)ion Nitric(V)acid (i)effervescence, fizzing, bubbles (ii)colourless gas produced that forms a white precipitate with lime water H3O+/H+(aq)ion All acids react with hydrogen carbonate/carbonate to form salt ,water and evolve/produce bubbles of carbon(IV)oxide and water. Carbon(IV)oxide forms a white precipitate when bubbled in lime water/extinguishes a burning splint. Alkanoic acids react with hydrogen carbonate/carbonate to form alkanoates ,water and evolve/produce bubbles of carbon(IV)oxide and water. Alkanoic acid + hydrogen carbonate -> alkanoate + water + carbon(IV)oxide Alkanoic acid + carbonate -> alkanoate + water + carbon(IV)oxide Examples 1. Sodium hydrogen carbonate reacts with ethanoic acid to form sodium ethanoate ,water and carbon(IV)oxide gas.


Alkanoic acids react with hydrogen carbonate/carbonate to form alkanoates ,water and evolve/produce bubbles of carbon(IV)oxide and water. Alkanoic acid + hydrogen carbonate -> alkanoate + water + carbon(IV)oxide Alkanoic acid + carbonate -> alkanoate + water + carbon(IV)oxide Examples 1. Sodium hydrogen carbonate reacts with ethanoic acid to form sodium ethanoate ,water and carbon(IV)oxide gas. CH3COOH (aq) + NaHCO3 (s) -> CH3COONa (aq) + H2O(l) + CO2 (g) (Ethanoic acid) (Sodium ethanoate) 2.Sodium carbonate reacts with ethanoic acid to form sodium ethanoate ,water and carbon(IV)oxide gas. 2CH3COOH (aq) + Na2CO3 (s) -> 2CH3COONa (aq) + H2O(l) + CO2 (g) (Ethanoic acid) (Sodium ethanoate) 3.Sodium carbonate reacts with ethan-1,2-dioic acid to form sodium ethanoate ,water and carbon(IV)oxide gas. HOOC-COOH+ Na2CO3 (s) -> NaOOC - COONa + H2O(l) + CO2 (g) (ethan-1,2-dioic acid) (sodium ethan-1,2-dioate) 4.Sodium hydrogen carbonate reacts with ethan-1,2-dioic acid to form sodium ethanoate ,water and carbon(IV)oxide gas. HOOC-COOH+ 2NaHCO3 (s) -> NaOOC - COONa + H2O(l) + 2CO2 (g) (ethan-1,2-dioic acid) (sodium ethan-1,2-dioate)
90 (e)Esterification Experiment Place 4cm3 of ethanol acid in a boiling tube. Add equal volume of ethanoic acid. To the mixture, add 2 drops of concentrated sulphuric(VI)acid carefully. Warm/heat gently on Bunsen flame. Pour the mixture into a beaker containing 50cm3 of water. Smell the products.


Warm/heat gently on Bunsen flame. Pour the mixture into a beaker containing 50cm3 of water. Smell the products. Repeat with a solution of succinic acid, citric acid, oxalic acid, tartaric acid and dilute sulphuric (VI) acid. Sample observations Solution/acid Observations Ethanoic acid Sweet fruity smell Succinic acid Sweet fruity smell Citric acid Sweet fruity smell Oxalic acid Sweet fruity smell Tartaric acid Sweet fruity smell Dilute sulphuric(VI)acid No sweet fruity smell Explanation Alkanols react with alkanoic acid to form the sweet smelling homologous series of esters and water.The reaction is catalysed by concentrated sulphuric(VI)acid in the laboratory but naturally by sunlight /heat.Each ester has a characteristic smell derived from the many possible combinations of alkanols and alkanoic acids. Alkanol + Alkanoic acids -> Ester + water Esters derive their names from the alkanol first then alkanoic acids. The alkanol “becomes” an alkyl group and the alkanoic acid “becomes” alkanoate hence alkylalkanoate. e.g. Ethanol + Ethanoic acid -> Ethylethanoate + Water Ethanol + Propanoic acid -> Ethylpropanoate + Water Ethanol + Methanoic acid -> Ethylmethanoate + Water Ethanol + butanoic acid -> Ethylbutanoate + Water Propanol + Ethanoic acid -> Propylethanoate + Water Methanol + Ethanoic acid -> Methyethanoate + Water Methanol + Decanoic acid -> Methyldecanoate + Water Decanol + Methanoic acid -> Decylmethanoate + Water
91 During the formation of the ester, the “O” joining the alkanol and alkanoic acid comes from the alkanol. R1 -COOH + R2 –OH -> R1 -COO –R2 + H2O Examples 1. Ethanol reacts with ethanoic acid to form the ester ethyl ethanoate and water. Ethanol + Ethanoic acid --Conc. H2SO4 -->Ethylethanoate + Water C2H5OH (l) + CH3COOH(l) --Conc.


H2SO4 --> CH3 CH2COO CH3(aq) +H2O(l) 5. Propanol reacts with propanoic acid to form the ester propylpropanoate and water. Propanol + Propanoic acid --Conc. H2SO4 -->Ethylethanoate + Water C3H7OH (l)+ CH3 CH2COOH(l) --Conc. H2SO4 -->CH3CH2COO C3H7(aq) +H2O(l) CH3CH2 CH2OH (l)+ CH3 CH2COOH(l) --Conc. H2SO4 --> CH3 CH2COOCH2 CH2CH3(aq) +H2O(l)
92 C. DETERGENTS Detergents are cleaning agents that improve the cleaning power /properties of water.A detergent therefore should be able to: (i)dissolve substances which water can not e.g grease ,oil, fat (ii)be washed away after cleaning. There are two types of detergents: (a)Soapy detergents (b)Soapless detergents (a) SOAPY DETERGENTS Soapy detergents usually called soap is long chain salt of organic alkanoic acids.Common soap is sodium octadecanoate .It is derived from reacting concentrated sodium hydroxide solution with octadecanoic acid(18 carbon alkanoic acid) i.e. Sodium hydroxide + octadecanoic acid -> Sodium octadecanoate + water NaOH(aq) + CH3 (CH2) 16 COOH(aq) -> CH3 (CH2) 16 COO – Na+ (aq) +H2 O(l) Commonly ,soap can thus be represented ; R- COO – Na+ where; R is a long chain alkyl group and -COO – Na+ is the alkanoate ion. In a school laboratory and at industrial and domestic level,soap is made by reacting concentrated sodium hydroxide solution with esters from (animal) fat and oil. The process of making soap is called saponification. During saponification ,the ester is hydrolyzed by the alkali to form sodium salt /soap and glycerol/propan-1,2,3-triol is produced.


In a school laboratory and at industrial and domestic level,soap is made by reacting concentrated sodium hydroxide solution with esters from (animal) fat and oil. The process of making soap is called saponification. During saponification ,the ester is hydrolyzed by the alkali to form sodium salt /soap and glycerol/propan-1,2,3-triol is produced. Fat/oil(ester)+sodium/potassium hydroxide->sodium/potassium salt(soap)+ glycerol Fats/Oils are esters with fatty acids and glycerol parts in their structure; C17H35COOCH2 C17H35COOCH C17H35COOCH2
93 When boiled with concentrated sodium hydroxide solution NaOH; (i)NaOH ionizes/dissociates into Na+ and OH- ions (ii)fat/oil split into three C17H35COO- and one CH2 CH CH2 (iii) the three Na+ combine with the three C17H35COO- to form the salt C17H35COO- Na+ (iv)the three OH-ions combine with the CH2 CH CH2 to form an alkanol with three functional groups CH2 OH CH OH CH2 OH(propan-1,2,3-triol) C17H35COOCH2 CH2OH C17H35COOCH +NaOH -> 3 C17H35COO- Na+ + CHOH C17H35COOCH2 CH2OH Ester Alkali Soap glycerol Generally: CnH2n+1COOCH2 CH2OH CnH2n+1COOCH +NaOH -> 3 CnH2n+1COO- Na+ + CHOH CnH2n+1COOCH2 CH2OH Ester Alkali Soap glycerol R - COOCH2 CH2OH R - COOCH +NaOH -> 3R-COO- Na+ + CHOH R- COOCH2 CH2OH Ester Alkali Soap glycerol During this process a little sodium chloride is added to precipitate the soap by reducing its solubility. This is called salting out. The soap is then added colouring agents ,perfumes and herbs of choice.


Fat/oil(ester)+sodium/potassium hydroxide->sodium/potassium salt(soap)+ glycerol Fats/Oils are esters with fatty acids and glycerol parts in their structure; C17H35COOCH2 C17H35COOCH C17H35COOCH2
93 When boiled with concentrated sodium hydroxide solution NaOH; (i)NaOH ionizes/dissociates into Na+ and OH- ions (ii)fat/oil split into three C17H35COO- and one CH2 CH CH2 (iii) the three Na+ combine with the three C17H35COO- to form the salt C17H35COO- Na+ (iv)the three OH-ions combine with the CH2 CH CH2 to form an alkanol with three functional groups CH2 OH CH OH CH2 OH(propan-1,2,3-triol) C17H35COOCH2 CH2OH C17H35COOCH +NaOH -> 3 C17H35COO- Na+ + CHOH C17H35COOCH2 CH2OH Ester Alkali Soap glycerol Generally: CnH2n+1COOCH2 CH2OH CnH2n+1COOCH +NaOH -> 3 CnH2n+1COO- Na+ + CHOH CnH2n+1COOCH2 CH2OH Ester Alkali Soap glycerol R - COOCH2 CH2OH R - COOCH +NaOH -> 3R-COO- Na+ + CHOH R- COOCH2 CH2OH Ester Alkali Soap glycerol During this process a little sodium chloride is added to precipitate the soap by reducing its solubility. This is called salting out. The soap is then added colouring agents ,perfumes and herbs of choice. School laboratory preparation of soap Place about 40 g of fatty (animal fat)beef/meat in 100cm3 beaker .Add about 15cm3 of 4.0M sodium hydroxide solution. Boil the mixture for about 15minutes.Stir the mixture .Add about 5.0cm3 of distilled water as you boil to make up for evaporation.


The soap is then added colouring agents ,perfumes and herbs of choice. School laboratory preparation of soap Place about 40 g of fatty (animal fat)beef/meat in 100cm3 beaker .Add about 15cm3 of 4.0M sodium hydroxide solution. Boil the mixture for about 15minutes.Stir the mixture .Add about 5.0cm3 of distilled water as you boil to make up for evaporation. Boil for about another 15minutes.Add about four spatula end full of pure sodium chloride crystals. Continue stirring for another five minutes. Allow to cool. Filter of
94 /decant and wash off the residue with distilled water .Transfer the clean residue into a dry beaker. Preserve. The action of soap Soapy detergents: (i)act by reducing the surface tension of water by forming a thin layer on top of the water. (ii)is made of a non-polar alkyl /hydrocarbon tail and a polar -COO-Na+ head. The non-polar alkyl /hydrocarbon tail is hydrophobic (water hating) and thus does not dissolve in water .It dissolves in non-polar solvent like grease, oil and fat. The polar -COO-Na+ head is hydrophilic (water loving)and thus dissolve in water. When washing with soapy detergent, the non-polar tail of the soapy detergent surround/dissolve in the dirt on the garment /grease/oil while the polar head dissolve in water. Through mechanical agitation/stirring/sqeezing/rubbing/beating/kneading, some grease is dislodged/lifted of the surface of the garment. It is immediately surrounded by more soap molecules It float and spread in the water as tiny droplets that scatter light in form of emulsion making the water cloudy and shinny. It is removed from the garment by rinsing with fresh water.The repulsion of the soap head prevent /ensure the droplets do not mix.Once removed, the dirt molecules cannot be redeposited back because it is surrounded by soap molecules. Advantages and disadvantages of using soapy detergents Soapy detergents are biodegradable. They are acted upon by bacteria and rot.They thus do not cause environmental pollution. Soapy detergents have the diadvatage in that: (i)they are made from fat and oils which are better eaten as food than make soap.


Advantages and disadvantages of using soapy detergents Soapy detergents are biodegradable. They are acted upon by bacteria and rot.They thus do not cause environmental pollution. Soapy detergents have the diadvatage in that: (i)they are made from fat and oils which are better eaten as food than make soap. (ii)forms an insoluble precipitate with hard water called scum. Scum is insoluble calcium octadecanoate and Magnesium octadecanoate formed when soap reacts with Ca2+ and Mg2+ present in hard water. Chemical equation 2C17H35COO- Na+ (aq) + Ca2+(aq) -> (C17H35COO- )Ca2+ (s) + 2Na+(aq) (insoluble Calcium octadecanote/scum) 2C17H35COO- Na+ (aq) + Mg2+(aq) -> (C17H35COO- )Mg2+ (s) + 2Na+(aq) (insoluble Magnesium octadecanote/scum) This causes wastage of soap. Potassium soaps are better than Sodium soap. Potassium is more expensive than sodium and thus its soap is also more expensive. (b)SOAPLESS DETERGENTS
95 Soapless detergent usually called detergent is a long chain salt fromed from byproducts of fractional distillation of crude oil.Commonly used soaps include: (i)washing agents (ii)toothpaste (iii)emulsifiers/wetting agents/shampoo Soapless detergents are derived from reacting: (i)concentrated sulphuric(VI)acid with a long chain alkanol e.g. Octadecanol(18 carbon alkanol) to form alkyl hydrogen sulphate(VI) Alkanol + Conc sulphuric(VI)acid -> alkyl hydrogen sulphate(VI) + Water R –OH + H2SO4 -> R –O-SO3H + H2O (ii)the alkyl hydrogen sulphate(VI) is then neutralized with sodium/potassium hydroxide to form sodium/potassium alkyl hydrogen sulphate(VI) Sodium/potassium alkyl hydrogen sulphate(VI) is the soapless detergent.


Potassium is more expensive than sodium and thus its soap is also more expensive. (b)SOAPLESS DETERGENTS
95 Soapless detergent usually called detergent is a long chain salt fromed from byproducts of fractional distillation of crude oil.Commonly used soaps include: (i)washing agents (ii)toothpaste (iii)emulsifiers/wetting agents/shampoo Soapless detergents are derived from reacting: (i)concentrated sulphuric(VI)acid with a long chain alkanol e.g. Octadecanol(18 carbon alkanol) to form alkyl hydrogen sulphate(VI) Alkanol + Conc sulphuric(VI)acid -> alkyl hydrogen sulphate(VI) + Water R –OH + H2SO4 -> R –O-SO3H + H2O (ii)the alkyl hydrogen sulphate(VI) is then neutralized with sodium/potassium hydroxide to form sodium/potassium alkyl hydrogen sulphate(VI) Sodium/potassium alkyl hydrogen sulphate(VI) is the soapless detergent. alkyl hydrogen + Potassium/sodium -> Sodium/potassium + Water sulphate(VI) hydroxide alkyl hydrogen sulphate(VI) R –O-SO3H + NaOH -> R –O-SO3- Na+ + H2O Example Step I : Reaction of Octadecanol with Conc.H2SO4 C17H35CH2OH (aq) + H2SO4 -> C17H35CH2-O- SO3- H+ (aq) + H2O (l) octadecanol + sulphuric(VI)acid -> Octadecyl hydrogen sulphate(VI) + water Step II: Neutralization by an alkali C17H35CH2-O- SO3- H+ (aq) + NaOH -> C17H35CH2-O- SO3- Na+ (aq) + H2O (l) Octadecyl hydrogen + sodium/potassium -> sodium/potassium octadecyl+Water sulphate(VI) hydroxide hydrogen sulphate(VI) School laboratory preparation of soapless detergent Place about 20g of olive oil in a 100cm3 beaker. Put it in a trough containing ice cold water.


Octadecanol(18 carbon alkanol) to form alkyl hydrogen sulphate(VI) Alkanol + Conc sulphuric(VI)acid -> alkyl hydrogen sulphate(VI) + Water R –OH + H2SO4 -> R –O-SO3H + H2O (ii)the alkyl hydrogen sulphate(VI) is then neutralized with sodium/potassium hydroxide to form sodium/potassium alkyl hydrogen sulphate(VI) Sodium/potassium alkyl hydrogen sulphate(VI) is the soapless detergent. alkyl hydrogen + Potassium/sodium -> Sodium/potassium + Water sulphate(VI) hydroxide alkyl hydrogen sulphate(VI) R –O-SO3H + NaOH -> R –O-SO3- Na+ + H2O Example Step I : Reaction of Octadecanol with Conc.H2SO4 C17H35CH2OH (aq) + H2SO4 -> C17H35CH2-O- SO3- H+ (aq) + H2O (l) octadecanol + sulphuric(VI)acid -> Octadecyl hydrogen sulphate(VI) + water Step II: Neutralization by an alkali C17H35CH2-O- SO3- H+ (aq) + NaOH -> C17H35CH2-O- SO3- Na+ (aq) + H2O (l) Octadecyl hydrogen + sodium/potassium -> sodium/potassium octadecyl+Water sulphate(VI) hydroxide hydrogen sulphate(VI) School laboratory preparation of soapless detergent Place about 20g of olive oil in a 100cm3 beaker. Put it in a trough containing ice cold water. Add dropwise carefully 18M concentrated sulphuric(VI)acid stirring continuously into the olive oil until the oil turns brown.Add 30cm3 of 6M sodium hydroxide solution.Stir.This is a soapless detergent. The action of soapless detergents
96 The action of soapless detergents is similar to that of soapy detergents.The soapless detergents contain the hydrophilic head and a long hydrophobic tail. i.e.


Add dropwise carefully 18M concentrated sulphuric(VI)acid stirring continuously into the olive oil until the oil turns brown.Add 30cm3 of 6M sodium hydroxide solution.Stir.This is a soapless detergent. The action of soapless detergents
96 The action of soapless detergents is similar to that of soapy detergents.The soapless detergents contain the hydrophilic head and a long hydrophobic tail. i.e. vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv-COO-Na+ vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv-O-SO3- Na+ (long hydrophobic /non-polar alkyl tail) (hydrophilic/polar/ionic head) The tail dissolves in fat/grease/oil while the ionic/polar/ionic head dissolves in water. The tail stick to the dirt which is removed by the attraction of water molecules and the polar/ionic/hydrophilic head by mechanical agitation /squeezing/kneading/ beating/rubbing/scrubbing/scatching. The suspended dirt is then surrounded by detergent molecules and repulsion of the anion head preventing the dirt from sticking on the material garment. The tiny droplets of dirt emulsion makes the water cloudy. On rinsing the cloudy emulsion is washed away. Advantages and disadvantages of using soapless detergents Soapless detergents are non-biodegradable unlike soapy detergents. They persist in water during sewage treatment by causing foaming in rivers ,lakes and streams leading to marine /aquatic death. Soapless detergents have the advantage in that they: (i)do not form scum with hard water. (ii)are cheap to manufacture/buying (iii)are made from petroleum products but soapis made from fats/oil for human consumption. Sample revision questions 1. Study the scheme below Fat/oil KOH Boiling Sodium Chloride Filtration Filtrate Y Residue X
97 (a)Identify the process Saponification (b)Fats and oils are esters.


(ii)are cheap to manufacture/buying (iii)are made from petroleum products but soapis made from fats/oil for human consumption. Sample revision questions 1. Study the scheme below Fat/oil KOH Boiling Sodium Chloride Filtration Filtrate Y Residue X
97 (a)Identify the process Saponification (b)Fats and oils are esters. Write the formula of the a common structure of ester C17H35COOCH2 C17H35COOCH C17H35COOCH2 (c)Write a balanced equation for the reaction taking place during boiling C17H35COOCH2 CH2OH C17H35COOCH +3NaOH -> 3 C17H35COO- Na+ + CHOH C17H35COOCH2 CH2OH Ester Alkali Soap glycerol (d)Give the IUPAC name of: (i)Residue X Potassium octadecanoate (ii)Filtrate Y Propan-1,2,3-triol (e)Give one use of fitrate Y Making paint (f)What is the function of sodium chloride To reduce the solubility of the soap hence helping in precipitating it out (g)Explain how residue X helps in washing. Has a non-polar hydrophobic tail that dissolves in dirt/grease /oil/fat Has a polar /ionic hydrophilic head that dissolves in water. 98 From mechanical agitation,the dirt is plucked out of the garment and surrounded by the tail end preventing it from being deposited back on the garment. (h)State one: (i)advantage of continued use of residue X on the environment Is biodegradable and thus do not pollute the environment (ii)disadvantage of using residue X Uses fat/oil during preparation/manufacture which are better used for human consumption. (i)Residue X was added dropwise to some water.The number of drops used before lather forms is as in the table below. Water sample A B C Drops of residue X 15 2 15 Drops of residue X in boiled water 2 2 15 (i)State and explain which sample of water is: I. Soft Sample B .Very little soap is used and no effect on amount of soap even on boiling/heating. II. Permanent hard Sample C .


Soft Sample B .Very little soap is used and no effect on amount of soap even on boiling/heating. II. Permanent hard Sample C . A lot of soap is used and no effect on amount of soap even on boiling/heating. Boiling does not remove permanent hardness of water. III. Temporary hard Sample A . A lot of soap is used before boiling. Very little soap is used on boiling/heating. Boiling remove temporary hardness of water. (ii)Write the equation for the reaction at water sample C. Chemical equation 2C17H35COO- K+ (aq) + CaSO4(aq) -> (C17H35COO- )Ca2+ (s) + K2SO4(aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Ca2+(aq) -> (C17H35COO- )Ca2+ (s) + 2K+(aq) (insoluble Calcium octadecanote/scum)
99 Chemical equation 2C17H35COO- K+ (aq) + MgSO4(aq) -> (C17H35COO- )Mg2+ (s) + K2SO4(aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Mg2+(aq) -> (C17H35COO- )Mg2+ (s) + 2K+(aq) (insoluble Magnesium octadecanote/scum) (iii)Write the equation for the reaction at water sample A before boiling.


Boiling remove temporary hardness of water. (ii)Write the equation for the reaction at water sample C. Chemical equation 2C17H35COO- K+ (aq) + CaSO4(aq) -> (C17H35COO- )Ca2+ (s) + K2SO4(aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Ca2+(aq) -> (C17H35COO- )Ca2+ (s) + 2K+(aq) (insoluble Calcium octadecanote/scum)
99 Chemical equation 2C17H35COO- K+ (aq) + MgSO4(aq) -> (C17H35COO- )Mg2+ (s) + K2SO4(aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Mg2+(aq) -> (C17H35COO- )Mg2+ (s) + 2K+(aq) (insoluble Magnesium octadecanote/scum) (iii)Write the equation for the reaction at water sample A before boiling. Chemical equation 2C17H35COO- K+ (aq) + Ca(HCO3)(aq) ->(C17H35COO- )Ca2+ (s) + 2KHCO3 (aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Ca2+(aq) -> (C17H35COO- )Ca2+ (s) + 2K+(aq) (insoluble Calcium octadecanote/scum) Chemical equation 2C17H35COO- K+ (aq) + Mg(HCO3)(aq) ->(C17H35COO- )Mg2+ (s) + 2KHCO3 (aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Mg2+(aq) -> (C17H35COO- )Mg2+ (s) + 2K+(aq) (insoluble Magnesium octadecanote/scum) (iv)Explain how water becomes hard Natural or rain water flowing /passing through rocks containing calcium (chalk, gypsum, limestone)and magnesium compounds (dolomite)dissolve them to form soluble Ca2+ and Mg2+ ions that causes water hardness.


(ii)Write the equation for the reaction at water sample C. Chemical equation 2C17H35COO- K+ (aq) + CaSO4(aq) -> (C17H35COO- )Ca2+ (s) + K2SO4(aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Ca2+(aq) -> (C17H35COO- )Ca2+ (s) + 2K+(aq) (insoluble Calcium octadecanote/scum)
99 Chemical equation 2C17H35COO- K+ (aq) + MgSO4(aq) -> (C17H35COO- )Mg2+ (s) + K2SO4(aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Mg2+(aq) -> (C17H35COO- )Mg2+ (s) + 2K+(aq) (insoluble Magnesium octadecanote/scum) (iii)Write the equation for the reaction at water sample A before boiling. Chemical equation 2C17H35COO- K+ (aq) + Ca(HCO3)(aq) ->(C17H35COO- )Ca2+ (s) + 2KHCO3 (aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Ca2+(aq) -> (C17H35COO- )Ca2+ (s) + 2K+(aq) (insoluble Calcium octadecanote/scum) Chemical equation 2C17H35COO- K+ (aq) + Mg(HCO3)(aq) ->(C17H35COO- )Mg2+ (s) + 2KHCO3 (aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Mg2+(aq) -> (C17H35COO- )Mg2+ (s) + 2K+(aq) (insoluble Magnesium octadecanote/scum) (iv)Explain how water becomes hard Natural or rain water flowing /passing through rocks containing calcium (chalk, gypsum, limestone)and magnesium compounds (dolomite)dissolve them to form soluble Ca2+ and Mg2+ ions that causes water hardness. (v)State two useful benefits of hard water -Used in bone and teeth formation -Coral polyps use hard water to form coral reefs -Snails use hard water to make their shells 2.Study the scheme below and use it to answer the questions that follow.


Chemical equation 2C17H35COO- K+ (aq) + CaSO4(aq) -> (C17H35COO- )Ca2+ (s) + K2SO4(aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Ca2+(aq) -> (C17H35COO- )Ca2+ (s) + 2K+(aq) (insoluble Calcium octadecanote/scum)
99 Chemical equation 2C17H35COO- K+ (aq) + MgSO4(aq) -> (C17H35COO- )Mg2+ (s) + K2SO4(aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Mg2+(aq) -> (C17H35COO- )Mg2+ (s) + 2K+(aq) (insoluble Magnesium octadecanote/scum) (iii)Write the equation for the reaction at water sample A before boiling. Chemical equation 2C17H35COO- K+ (aq) + Ca(HCO3)(aq) ->(C17H35COO- )Ca2+ (s) + 2KHCO3 (aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Ca2+(aq) -> (C17H35COO- )Ca2+ (s) + 2K+(aq) (insoluble Calcium octadecanote/scum) Chemical equation 2C17H35COO- K+ (aq) + Mg(HCO3)(aq) ->(C17H35COO- )Mg2+ (s) + 2KHCO3 (aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Mg2+(aq) -> (C17H35COO- )Mg2+ (s) + 2K+(aq) (insoluble Magnesium octadecanote/scum) (iv)Explain how water becomes hard Natural or rain water flowing /passing through rocks containing calcium (chalk, gypsum, limestone)and magnesium compounds (dolomite)dissolve them to form soluble Ca2+ and Mg2+ ions that causes water hardness. (v)State two useful benefits of hard water -Used in bone and teeth formation -Coral polyps use hard water to form coral reefs -Snails use hard water to make their shells 2.Study the scheme below and use it to answer the questions that follow. Olive oil Conc.


Chemical equation 2C17H35COO- K+ (aq) + Ca(HCO3)(aq) ->(C17H35COO- )Ca2+ (s) + 2KHCO3 (aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Ca2+(aq) -> (C17H35COO- )Ca2+ (s) + 2K+(aq) (insoluble Calcium octadecanote/scum) Chemical equation 2C17H35COO- K+ (aq) + Mg(HCO3)(aq) ->(C17H35COO- )Mg2+ (s) + 2KHCO3 (aq) (insoluble Calcium octadecanote/scum) Ionic equation 2C17H35COO- K+ (aq) + Mg2+(aq) -> (C17H35COO- )Mg2+ (s) + 2K+(aq) (insoluble Magnesium octadecanote/scum) (iv)Explain how water becomes hard Natural or rain water flowing /passing through rocks containing calcium (chalk, gypsum, limestone)and magnesium compounds (dolomite)dissolve them to form soluble Ca2+ and Mg2+ ions that causes water hardness. (v)State two useful benefits of hard water -Used in bone and teeth formation -Coral polyps use hard water to form coral reefs -Snails use hard water to make their shells 2.Study the scheme below and use it to answer the questions that follow. Olive oil Conc. H2SO4 Ice cold water Brown solid A 6M sodium hydroxide Substance B
100 (a)Identify : (i)brown solid A Alkyl hydrogen sulphate(VI) (ii)substance B Sodium alkyl hydrogen sulphate(VI) (b)Write a general formula of: (i)Substance A.


(v)State two useful benefits of hard water -Used in bone and teeth formation -Coral polyps use hard water to form coral reefs -Snails use hard water to make their shells 2.Study the scheme below and use it to answer the questions that follow. Olive oil Conc. H2SO4 Ice cold water Brown solid A 6M sodium hydroxide Substance B
100 (a)Identify : (i)brown solid A Alkyl hydrogen sulphate(VI) (ii)substance B Sodium alkyl hydrogen sulphate(VI) (b)Write a general formula of: (i)Substance A. O R-O-S O3 H // R- O - S - O - H O (ii)Substance B O R-O-S O3 - Na+ R- O - S - O - Na+ O (c)State one (i) advantage of continued use of substance B -Does not form scum with hard water -Is cheap to make -Does not use food for human as a raw material. (ii)disadvantage of continued use of substance B. Is non-biodegradable therefore do not pollute the environment (d)Explain the action of B during washing. Has a non-polar hydrocarbon long tail that dissolves in dirt/grease/oil/fat. Has a polar/ionic hydrophilic head that dissolves in water Through mechanical agitation the dirt is plucked /removed from the garment and surrounded by the tail end preventing it from being deposited back on the garment. (e) Ethene was substituted for olive oil in the above process. Write the equation and name of the new products A and B. 101 Product A Ethene + Sulphuric(VI)acid -> Ethyl hydrogen sulphate(VI) H2C=CH2 + H2SO4 –> H3C – CH2 –O-SO3H Product B Ethyl hydrogen sulphate(VI) + sodium hydroxide -> sodium Ethyl + Water hydrogen sulphate(VI) H3C – CH2 –O-SO3H + NaOH -> H3C – CH2 –O-SO3-Na+ + H2O (f)Ethanol can also undergo similar reactions forming new products A and B.Show this using a chemical equation.


(e) Ethene was substituted for olive oil in the above process. Write the equation and name of the new products A and B. 101 Product A Ethene + Sulphuric(VI)acid -> Ethyl hydrogen sulphate(VI) H2C=CH2 + H2SO4 –> H3C – CH2 –O-SO3H Product B Ethyl hydrogen sulphate(VI) + sodium hydroxide -> sodium Ethyl + Water hydrogen sulphate(VI) H3C – CH2 –O-SO3H + NaOH -> H3C – CH2 –O-SO3-Na+ + H2O (f)Ethanol can also undergo similar reactions forming new products A and B.Show this using a chemical equation. Product A Ethanol + Sulphuric(VI)acid ->Ethyl hydrogen sulphate(VI) + water H3C-CH2OH + H2SO4 –> H3C – CH2 –O-SO3H + H2O Product B Ethyl hydrogen sulphate(VI) + sodium hydroxide -> sodium Ethyl + Water hydrogen sulphate(VI) H3C – CH2 –O-SO3H + NaOH -> H3C – CH2 –O-SO3-Na+ + H2O 3.Below is part of a detergent H3C – (CH2 )16 – O - SO3 - K + (a)Write the formular of the polar and non-polar end Polar end H3C – (CH2 )16 – Non-polar end – O - SO3 - K + (b)Is the molecule a soapy or saopless detergent? Soapless detergent (c)State one advantage of using the above detergent -does not form scum with hard water -is cheap to manufacture 4.The structure of a detergent is H H H H H H H H H H H H H
102 H- C- C- C-C- C- C- C- C- C- C -C- C- -C- COO-Na+ H H H H H H H H H H H H H a) Write the molecular formula of the detergent. (1mk) CH3(CH2)12COO-Na+ b) What type of detergent is represented by the formula?


Product A Ethanol + Sulphuric(VI)acid ->Ethyl hydrogen sulphate(VI) + water H3C-CH2OH + H2SO4 –> H3C – CH2 –O-SO3H + H2O Product B Ethyl hydrogen sulphate(VI) + sodium hydroxide -> sodium Ethyl + Water hydrogen sulphate(VI) H3C – CH2 –O-SO3H + NaOH -> H3C – CH2 –O-SO3-Na+ + H2O 3.Below is part of a detergent H3C – (CH2 )16 – O - SO3 - K + (a)Write the formular of the polar and non-polar end Polar end H3C – (CH2 )16 – Non-polar end – O - SO3 - K + (b)Is the molecule a soapy or saopless detergent? Soapless detergent (c)State one advantage of using the above detergent -does not form scum with hard water -is cheap to manufacture 4.The structure of a detergent is H H H H H H H H H H H H H
102 H- C- C- C-C- C- C- C- C- C- C -C- C- -C- COO-Na+ H H H H H H H H H H H H H a) Write the molecular formula of the detergent. (1mk) CH3(CH2)12COO-Na+ b) What type of detergent is represented by the formula? (1mk) Soapy detergent c) When this type of detergent is used to wash linen in hard water, spots (marks) are left on the linen. Write the formula of the substance responsible for the spots (CH3(CH2)12COO-)2Ca2+ / CH3(CH2)12COO-)2Mg2+ D. POLYMERS AND FIBRES Polymers and fibres are giant molecules of organic compounds. Polymers and fibres are formed when small molecules called monomers join together to form large molecules called polymers at high temperatures and pressures. This process is called polymerization.


POLYMERS AND FIBRES Polymers and fibres are giant molecules of organic compounds. Polymers and fibres are formed when small molecules called monomers join together to form large molecules called polymers at high temperatures and pressures. This process is called polymerization. Polymers and fibres are either: (a)Natural polymers and fibres (b)Synthetic polymers and fibres Natural polymers and fibres are found in living things(plants and animals) Natural polymers/fibres include: -proteins/polypeptides making amino acids in animals -cellulose that make cotton,wool,paper and silk -Starch that come from glucose -Fats and oils -Rubber from latex in rubber trees. Synthetic polymers and fibres are man-made. They include: -polyethene
103 -polychloroethene -polyphenylethene(polystyrene) -Terylene(Dacron) -Nylon-6,6 -Perspex(artificial glass) Synthetic polymers and fibres have the following characteristic advantages over natural polymers 1. They are light and portable 2. They are easy to manufacture. 3. They can easily be molded into shape of choice. 4. They are resistant to corrosion, water, air , acids, bases and salts. 5. They are comparatively cheap, affordable, colourful and aesthetic Synthetic polymers and fibres however have the following disadvantages over natural polymers 1. They are non-biodegradable and hence cause environmental pollution during disposal 2. They give out highly poisonous gases when burnt like chlorine/carbon(II)oxide 3. Some on burning produce Carbon(IV)oxide. Carbon(IV)oxide is a green house gas that cause global warming. 4. Compared to some metals, they are poor conductors of heat,electricity and have lower tensile strength. 5. To reduce environmental pollution from synthetic polymers and fibres, the followitn methods of disposal should be used: 1.Recycling: Once produced all synthetic polymers and fibres should be recycled to a new product. This prevents accumulation of the synthetic polymers and fibres in the environment. 2.Production of biodegradable synthetic polymers and fibres that rot away.


To reduce environmental pollution from synthetic polymers and fibres, the followitn methods of disposal should be used: 1.Recycling: Once produced all synthetic polymers and fibres should be recycled to a new product. This prevents accumulation of the synthetic polymers and fibres in the environment. 2.Production of biodegradable synthetic polymers and fibres that rot away. There are two types of polymerization: (a)addition polymerization (b)condensation polymerization (a)addition polymerization Addition polymerization is the process where a small unsaturated monomer (alkene ) molecule join together to form a large saturated molecule. Only alkenes undergo addition polymerization. 104 Addition polymers are named from the alkene/monomer making the polymer and adding the prefix “poly” before the name of monomer to form a polyalkene During addition polymerization (i)the double bond in alkenes break (ii)free radicals are formed (iii)the free radicals collide with each other and join to form a larger molecule. The more collisions the larger the molecule. Examples of addition polymerization 1.Formation of Polyethene Polyethene is an addition polymer formed when ethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting paticles) H H H H H H H H C = C + C = C + C = C + C = C + … H H H H H H H H Ethene + Ethene + Ethene + Ethene + … (ii)the double bond joining the ethane molecule break to free readicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H H H H H H H H Ethene radical + Ethene radical + Ethene radical + Ethene radical + … (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons
105 •C – C - C – C - C – C - C - C• + … H H H H H H H H Lone pair of electrons can be used to join more monomers to form longer polyethene.


The more collisions the larger the molecule. Examples of addition polymerization 1.Formation of Polyethene Polyethene is an addition polymer formed when ethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting paticles) H H H H H H H H C = C + C = C + C = C + C = C + … H H H H H H H H Ethene + Ethene + Ethene + Ethene + … (ii)the double bond joining the ethane molecule break to free readicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H H H H H H H H Ethene radical + Ethene radical + Ethene radical + Ethene radical + … (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons
105 •C – C - C – C - C – C - C - C• + … H H H H H H H H Lone pair of electrons can be used to join more monomers to form longer polyethene. Polyethene molecule can be represented as: H H H H H H H H extension of molecule/polymer - C – C - C – C - C – C - C – C- + … H H H H H H H H Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H H Where n is the number of monomers in the polymer.


Examples of addition polymerization 1.Formation of Polyethene Polyethene is an addition polymer formed when ethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting paticles) H H H H H H H H C = C + C = C + C = C + C = C + … H H H H H H H H Ethene + Ethene + Ethene + Ethene + … (ii)the double bond joining the ethane molecule break to free readicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H H H H H H H H Ethene radical + Ethene radical + Ethene radical + Ethene radical + … (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons
105 •C – C - C – C - C – C - C - C• + … H H H H H H H H Lone pair of electrons can be used to join more monomers to form longer polyethene. Polyethene molecule can be represented as: H H H H H H H H extension of molecule/polymer - C – C - C – C - C – C - C – C- + … H H H H H H H H Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H H Where n is the number of monomers in the polymer. The number of monomers in the polymer can be determined from the molar mass of the polymer and monomer from the relationship: Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer Examples Polythene has a molar mass of 4760.Calculate the number of ethene molecules in the polymer(C=12.0, H=1.0 ) Number of monomers/repeating units in polyomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C2H4 )= 28 Molar mass polyethene = 4760 Substituting 4760 = 170 ethene molecules 28 The commercial name of polyethene is polythene.


During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting paticles) H H H H H H H H C = C + C = C + C = C + C = C + … H H H H H H H H Ethene + Ethene + Ethene + Ethene + … (ii)the double bond joining the ethane molecule break to free readicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H H H H H H H H Ethene radical + Ethene radical + Ethene radical + Ethene radical + … (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons
105 •C – C - C – C - C – C - C - C• + … H H H H H H H H Lone pair of electrons can be used to join more monomers to form longer polyethene. Polyethene molecule can be represented as: H H H H H H H H extension of molecule/polymer - C – C - C – C - C – C - C – C- + … H H H H H H H H Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H H Where n is the number of monomers in the polymer. The number of monomers in the polymer can be determined from the molar mass of the polymer and monomer from the relationship: Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer Examples Polythene has a molar mass of 4760.Calculate the number of ethene molecules in the polymer(C=12.0, H=1.0 ) Number of monomers/repeating units in polyomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C2H4 )= 28 Molar mass polyethene = 4760 Substituting 4760 = 170 ethene molecules 28 The commercial name of polyethene is polythene. It is an elastic, tough, transparent and durable plastic.


Polyethene molecule can be represented as: H H H H H H H H extension of molecule/polymer - C – C - C – C - C – C - C – C- + … H H H H H H H H Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H H Where n is the number of monomers in the polymer. The number of monomers in the polymer can be determined from the molar mass of the polymer and monomer from the relationship: Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer Examples Polythene has a molar mass of 4760.Calculate the number of ethene molecules in the polymer(C=12.0, H=1.0 ) Number of monomers/repeating units in polyomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C2H4 )= 28 Molar mass polyethene = 4760 Substituting 4760 = 170 ethene molecules 28 The commercial name of polyethene is polythene. It is an elastic, tough, transparent and durable plastic. Polythene is used: (i)in making plastic bag (ii)bowls and plastic bags (iii)packaging materials
106 2.Formation of Polychlorethene Polychloroethene is an addition polymer formed when chloroethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure.


The number of monomers in the polymer can be determined from the molar mass of the polymer and monomer from the relationship: Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer Examples Polythene has a molar mass of 4760.Calculate the number of ethene molecules in the polymer(C=12.0, H=1.0 ) Number of monomers/repeating units in polyomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C2H4 )= 28 Molar mass polyethene = 4760 Substituting 4760 = 170 ethene molecules 28 The commercial name of polyethene is polythene. It is an elastic, tough, transparent and durable plastic. Polythene is used: (i)in making plastic bag (ii)bowls and plastic bags (iii)packaging materials
106 2.Formation of Polychlorethene Polychloroethene is an addition polymer formed when chloroethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) H H H H H H H H C = C + C = C + C = C + C = C + … H Cl H Cl H Cl H Cl chloroethene + chloroethene + chloroethene + chloroethene + … (ii)the double bond joining the chloroethene molecule break to free radicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H Cl H Cl H Cl H Cl (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons •C – C - C – C - C – C - C - C• + … H Cl H Cl H Cl H Cl Lone pair of electrons can be used to join more monomers to form longer polychloroethene.


It is an elastic, tough, transparent and durable plastic. Polythene is used: (i)in making plastic bag (ii)bowls and plastic bags (iii)packaging materials
106 2.Formation of Polychlorethene Polychloroethene is an addition polymer formed when chloroethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) H H H H H H H H C = C + C = C + C = C + C = C + … H Cl H Cl H Cl H Cl chloroethene + chloroethene + chloroethene + chloroethene + … (ii)the double bond joining the chloroethene molecule break to free radicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H Cl H Cl H Cl H Cl (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons •C – C - C – C - C – C - C - C• + … H Cl H Cl H Cl H Cl Lone pair of electrons can be used to join more monomers to form longer polychloroethene. Polychloroethene molecule can be represented as: H H H H H H H H extension of molecule/polymer - C – C - C – C - C – C - C – C- + …
107 H Cl H Cl H Cl H Cl Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H Cl Examples Polychlorothene has a molar mass of 4760.Calculate the number of chlorethene molecules in the polymer(C=12.0, H=1.0,Cl=35.5 ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C2H3Cl )= 62.5 Molar mass polyethene = 4760 Substituting 4760 = 77.16 => 77 polychloroethene molecules(whole number) 62.5 The commercial name of polychloroethene is polyvinylchloride(PVC).


Polythene is used: (i)in making plastic bag (ii)bowls and plastic bags (iii)packaging materials
106 2.Formation of Polychlorethene Polychloroethene is an addition polymer formed when chloroethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) H H H H H H H H C = C + C = C + C = C + C = C + … H Cl H Cl H Cl H Cl chloroethene + chloroethene + chloroethene + chloroethene + … (ii)the double bond joining the chloroethene molecule break to free radicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H Cl H Cl H Cl H Cl (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons •C – C - C – C - C – C - C - C• + … H Cl H Cl H Cl H Cl Lone pair of electrons can be used to join more monomers to form longer polychloroethene. Polychloroethene molecule can be represented as: H H H H H H H H extension of molecule/polymer - C – C - C – C - C – C - C – C- + …
107 H Cl H Cl H Cl H Cl Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H Cl Examples Polychlorothene has a molar mass of 4760.Calculate the number of chlorethene molecules in the polymer(C=12.0, H=1.0,Cl=35.5 ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C2H3Cl )= 62.5 Molar mass polyethene = 4760 Substituting 4760 = 77.16 => 77 polychloroethene molecules(whole number) 62.5 The commercial name of polychloroethene is polyvinylchloride(PVC). It is a tough, non-transparent and durable plastic.


During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) H H H H H H H H C = C + C = C + C = C + C = C + … H Cl H Cl H Cl H Cl chloroethene + chloroethene + chloroethene + chloroethene + … (ii)the double bond joining the chloroethene molecule break to free radicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H Cl H Cl H Cl H Cl (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons •C – C - C – C - C – C - C - C• + … H Cl H Cl H Cl H Cl Lone pair of electrons can be used to join more monomers to form longer polychloroethene. Polychloroethene molecule can be represented as: H H H H H H H H extension of molecule/polymer - C – C - C – C - C – C - C – C- + …
107 H Cl H Cl H Cl H Cl Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H Cl Examples Polychlorothene has a molar mass of 4760.Calculate the number of chlorethene molecules in the polymer(C=12.0, H=1.0,Cl=35.5 ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C2H3Cl )= 62.5 Molar mass polyethene = 4760 Substituting 4760 = 77.16 => 77 polychloroethene molecules(whole number) 62.5 The commercial name of polychloroethene is polyvinylchloride(PVC). It is a tough, non-transparent and durable plastic. PVC is used: (i)in making plastic rope (ii)water pipes (iii)crates and boxes 3.Formation of Polyphenylethene Polyphenylethene is an addition polymer formed when phenylethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure.


Polychloroethene molecule can be represented as: H H H H H H H H extension of molecule/polymer - C – C - C – C - C – C - C – C- + …
107 H Cl H Cl H Cl H Cl Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H Cl Examples Polychlorothene has a molar mass of 4760.Calculate the number of chlorethene molecules in the polymer(C=12.0, H=1.0,Cl=35.5 ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C2H3Cl )= 62.5 Molar mass polyethene = 4760 Substituting 4760 = 77.16 => 77 polychloroethene molecules(whole number) 62.5 The commercial name of polychloroethene is polyvinylchloride(PVC). It is a tough, non-transparent and durable plastic. PVC is used: (i)in making plastic rope (ii)water pipes (iii)crates and boxes 3.Formation of Polyphenylethene Polyphenylethene is an addition polymer formed when phenylethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) H H H H H H H H C = C + C = C + C = C + C = C + … H C6H5 H C6H5 H C6H5 H C6H5 phenylethene + phenylethene + phenylethene + phenylethene + …
108 (ii)the double bond joining the phenylethene molecule break to free radicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H C6H5 H C6H5 H C6H5 H C6H5 (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons • C – C - C – C - C – C - C - C • + … H C6H5 H C6H5 H C6H5 H C6H5 Lone pair of electrons can be used to join more monomers to form longer polyphenylethene.


It is a tough, non-transparent and durable plastic. PVC is used: (i)in making plastic rope (ii)water pipes (iii)crates and boxes 3.Formation of Polyphenylethene Polyphenylethene is an addition polymer formed when phenylethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) H H H H H H H H C = C + C = C + C = C + C = C + … H C6H5 H C6H5 H C6H5 H C6H5 phenylethene + phenylethene + phenylethene + phenylethene + …
108 (ii)the double bond joining the phenylethene molecule break to free radicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H C6H5 H C6H5 H C6H5 H C6H5 (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons • C – C - C – C - C – C - C - C • + … H C6H5 H C6H5 H C6H5 H C6H5 Lone pair of electrons can be used to join more monomers to form longer polyphenylethene. Polyphenylethene molecule can be represented as: H H H H H H H H - C – C - C – C - C – C - C - C - H C6H5 H C6H5 H C6H5 H C6H5 Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H C6H5 Examples Polyphenylthene has a molar mass of 4760.Calculate the number of phenylethene molecules in the polymer(C=12.0, H=1.0, ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C8H8 )= 104 Molar mass polyethene = 4760 Substituting 4760 = 45.7692 =>45 polyphenylethene molecules(whole number)
109 104 The commercial name of polyphenylethene is polystyrene.


PVC is used: (i)in making plastic rope (ii)water pipes (iii)crates and boxes 3.Formation of Polyphenylethene Polyphenylethene is an addition polymer formed when phenylethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) H H H H H H H H C = C + C = C + C = C + C = C + … H C6H5 H C6H5 H C6H5 H C6H5 phenylethene + phenylethene + phenylethene + phenylethene + …
108 (ii)the double bond joining the phenylethene molecule break to free radicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H C6H5 H C6H5 H C6H5 H C6H5 (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons • C – C - C – C - C – C - C - C • + … H C6H5 H C6H5 H C6H5 H C6H5 Lone pair of electrons can be used to join more monomers to form longer polyphenylethene. Polyphenylethene molecule can be represented as: H H H H H H H H - C – C - C – C - C – C - C - C - H C6H5 H C6H5 H C6H5 H C6H5 Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H C6H5 Examples Polyphenylthene has a molar mass of 4760.Calculate the number of phenylethene molecules in the polymer(C=12.0, H=1.0, ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C8H8 )= 104 Molar mass polyethene = 4760 Substituting 4760 = 45.7692 =>45 polyphenylethene molecules(whole number)
109 104 The commercial name of polyphenylethene is polystyrene. It is a very light durable plastic.


During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) H H H H H H H H C = C + C = C + C = C + C = C + … H C6H5 H C6H5 H C6H5 H C6H5 phenylethene + phenylethene + phenylethene + phenylethene + …
108 (ii)the double bond joining the phenylethene molecule break to free radicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H C6H5 H C6H5 H C6H5 H C6H5 (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons • C – C - C – C - C – C - C - C • + … H C6H5 H C6H5 H C6H5 H C6H5 Lone pair of electrons can be used to join more monomers to form longer polyphenylethene. Polyphenylethene molecule can be represented as: H H H H H H H H - C – C - C – C - C – C - C - C - H C6H5 H C6H5 H C6H5 H C6H5 Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H C6H5 Examples Polyphenylthene has a molar mass of 4760.Calculate the number of phenylethene molecules in the polymer(C=12.0, H=1.0, ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C8H8 )= 104 Molar mass polyethene = 4760 Substituting 4760 = 45.7692 =>45 polyphenylethene molecules(whole number)
109 104 The commercial name of polyphenylethene is polystyrene. It is a very light durable plastic. Polystyrene is used: (i)in making packaging material for carrying delicate items like computers, radion,calculators.


Polyphenylethene molecule can be represented as: H H H H H H H H - C – C - C – C - C – C - C - C - H C6H5 H C6H5 H C6H5 H C6H5 Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H C6H5 Examples Polyphenylthene has a molar mass of 4760.Calculate the number of phenylethene molecules in the polymer(C=12.0, H=1.0, ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C8H8 )= 104 Molar mass polyethene = 4760 Substituting 4760 = 45.7692 =>45 polyphenylethene molecules(whole number)
109 104 The commercial name of polyphenylethene is polystyrene. It is a very light durable plastic. Polystyrene is used: (i)in making packaging material for carrying delicate items like computers, radion,calculators. (ii)ceiling tiles (iii)clothe linings 4.Formation of Polypropene Polypropene is an addition polymer formed when propene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure.


It is a very light durable plastic. Polystyrene is used: (i)in making packaging material for carrying delicate items like computers, radion,calculators. (ii)ceiling tiles (iii)clothe linings 4.Formation of Polypropene Polypropene is an addition polymer formed when propene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) H H H H H H H H C = C + C = C + C = C + C = C + … H CH3 H CH3 H CH3 H CH3 propene + propene + propene + propene + … (ii)the double bond joining the phenylethene molecule break to free radicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H CH3 H CH3 H CH3 H CH3 (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons • C – C - C – C - C – C - C - C • + … H CH3 H CH3 H CH3 H CH3 Lone pair of electrons can be used to join more monomers to form longer propene. propene molecule can be represented as:
110 H H H H H H H H - C – C - C – C - C – C - C - C - H CH3 H CH3 H CH3 H CH3 Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H CH3 Examples Polypropene has a molar mass of 4760.Calculate the number of propene molecules in the polymer(C=12.0, H=1.0, ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass propene (C3H8 )= 44 Molar mass polyethene = 4760 Substituting 4760 = 108.1818 =>108 propene molecules(whole number) 44 The commercial name of polyphenylethene is polystyrene. It is a very light durable plastic.


During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) H H H H H H H H C = C + C = C + C = C + C = C + … H CH3 H CH3 H CH3 H CH3 propene + propene + propene + propene + … (ii)the double bond joining the phenylethene molecule break to free radicals H H H H H H H H •C – C• + •C - C• + •C - C• + •C - C• + … H CH3 H CH3 H CH3 H CH3 (iii)the free radicals collide with each other and join to form a larger molecule H H H H H H H H lone pair of electrons • C – C - C – C - C – C - C - C • + … H CH3 H CH3 H CH3 H CH3 Lone pair of electrons can be used to join more monomers to form longer propene. propene molecule can be represented as:
110 H H H H H H H H - C – C - C – C - C – C - C - C - H CH3 H CH3 H CH3 H CH3 Since the molecule is a repetition of one monomer, then the polymer is: H H ( C – C )n H CH3 Examples Polypropene has a molar mass of 4760.Calculate the number of propene molecules in the polymer(C=12.0, H=1.0, ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass propene (C3H8 )= 44 Molar mass polyethene = 4760 Substituting 4760 = 108.1818 =>108 propene molecules(whole number) 44 The commercial name of polyphenylethene is polystyrene. It is a very light durable plastic. Polystyrene is used: (i)in making packaging material for carrying delicate items like computers, radion,calculators. (ii)ceiling tiles (iii)clothe linings 5.Formation of Polytetrafluorothene Polytetrafluorothene is an addition polymer formed when tetrafluoroethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure.


It is a very light durable plastic. Polystyrene is used: (i)in making packaging material for carrying delicate items like computers, radion,calculators. (ii)ceiling tiles (iii)clothe linings 5.Formation of Polytetrafluorothene Polytetrafluorothene is an addition polymer formed when tetrafluoroethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) F F F F F F F F
111 C = C + C = C + C = C + C = C + … F F F F F F F F tetrafluoroethene + tetrafluoroethene+ tetrafluoroethene+ tetrafluoroethene + … (ii)the double bond joining the tetrafluoroethene molecule break to free radicals F F F F F F F F •C – C• + •C - C• + •C - C• + •C - C• + … F F F F F F F F (iii)the free radicals collide with each other and join to form a larger molecule F F F F F F F F lone pair of electrons •C – C - C – C - C – C - C - C• + … F F F F F F F F Lone pair of electrons can be used to join more monomers to form longer polytetrafluoroethene.


Polystyrene is used: (i)in making packaging material for carrying delicate items like computers, radion,calculators. (ii)ceiling tiles (iii)clothe linings 5.Formation of Polytetrafluorothene Polytetrafluorothene is an addition polymer formed when tetrafluoroethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) F F F F F F F F
111 C = C + C = C + C = C + C = C + … F F F F F F F F tetrafluoroethene + tetrafluoroethene+ tetrafluoroethene+ tetrafluoroethene + … (ii)the double bond joining the tetrafluoroethene molecule break to free radicals F F F F F F F F •C – C• + •C - C• + •C - C• + •C - C• + … F F F F F F F F (iii)the free radicals collide with each other and join to form a larger molecule F F F F F F F F lone pair of electrons •C – C - C – C - C – C - C - C• + … F F F F F F F F Lone pair of electrons can be used to join more monomers to form longer polytetrafluoroethene. polytetrafluoroethene molecule can be represented as: F F F F F F F F extension of molecule/polymer - C – C - C – C - C – C - C – C- + … F F F F F F F F Since the molecule is a repetition of one monomer, then the polymer is: F F ( C – C )n F F Examples
112 Polytetrafluorothene has a molar mass of 4760.Calculate the number of tetrafluoroethene molecules in the polymer(C=12.0, ,F=19 ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C2F4 )= 62.5 Molar mass polyethene = 4760 Substituting 4760 = 77.16 => 77 polychloroethene molecules(whole number) 62.5 The commercial name of polytetrafluorethene(P.T.F.E) is Teflon(P.T.F.E).


(ii)ceiling tiles (iii)clothe linings 5.Formation of Polytetrafluorothene Polytetrafluorothene is an addition polymer formed when tetrafluoroethene molecule/monomer join together to form a large molecule/polymer at high temperatures and pressure. During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) F F F F F F F F
111 C = C + C = C + C = C + C = C + … F F F F F F F F tetrafluoroethene + tetrafluoroethene+ tetrafluoroethene+ tetrafluoroethene + … (ii)the double bond joining the tetrafluoroethene molecule break to free radicals F F F F F F F F •C – C• + •C - C• + •C - C• + •C - C• + … F F F F F F F F (iii)the free radicals collide with each other and join to form a larger molecule F F F F F F F F lone pair of electrons •C – C - C – C - C – C - C - C• + … F F F F F F F F Lone pair of electrons can be used to join more monomers to form longer polytetrafluoroethene. polytetrafluoroethene molecule can be represented as: F F F F F F F F extension of molecule/polymer - C – C - C – C - C – C - C – C- + … F F F F F F F F Since the molecule is a repetition of one monomer, then the polymer is: F F ( C – C )n F F Examples
112 Polytetrafluorothene has a molar mass of 4760.Calculate the number of tetrafluoroethene molecules in the polymer(C=12.0, ,F=19 ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C2F4 )= 62.5 Molar mass polyethene = 4760 Substituting 4760 = 77.16 => 77 polychloroethene molecules(whole number) 62.5 The commercial name of polytetrafluorethene(P.T.F.E) is Teflon(P.T.F.E). It is a tough, non-transparent and durable plastic.


During polymerization: (i)many molecules are brought nearer to each other by the high pressure(which reduces the volume occupied by reacting particles) F F F F F F F F
111 C = C + C = C + C = C + C = C + … F F F F F F F F tetrafluoroethene + tetrafluoroethene+ tetrafluoroethene+ tetrafluoroethene + … (ii)the double bond joining the tetrafluoroethene molecule break to free radicals F F F F F F F F •C – C• + •C - C• + •C - C• + •C - C• + … F F F F F F F F (iii)the free radicals collide with each other and join to form a larger molecule F F F F F F F F lone pair of electrons •C – C - C – C - C – C - C - C• + … F F F F F F F F Lone pair of electrons can be used to join more monomers to form longer polytetrafluoroethene. polytetrafluoroethene molecule can be represented as: F F F F F F F F extension of molecule/polymer - C – C - C – C - C – C - C – C- + … F F F F F F F F Since the molecule is a repetition of one monomer, then the polymer is: F F ( C – C )n F F Examples
112 Polytetrafluorothene has a molar mass of 4760.Calculate the number of tetrafluoroethene molecules in the polymer(C=12.0, ,F=19 ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C2F4 )= 62.5 Molar mass polyethene = 4760 Substituting 4760 = 77.16 => 77 polychloroethene molecules(whole number) 62.5 The commercial name of polytetrafluorethene(P.T.F.E) is Teflon(P.T.F.E). It is a tough, non-transparent and durable plastic. PVC is used: (i)in making plastic rope (ii)water pipes (iii)crates and boxes 5.Formation of rubber from Latex Natural rubber is obtained from rubber trees.


polytetrafluoroethene molecule can be represented as: F F F F F F F F extension of molecule/polymer - C – C - C – C - C – C - C – C- + … F F F F F F F F Since the molecule is a repetition of one monomer, then the polymer is: F F ( C – C )n F F Examples
112 Polytetrafluorothene has a molar mass of 4760.Calculate the number of tetrafluoroethene molecules in the polymer(C=12.0, ,F=19 ) Number of monomers/repeating units in monomer = Molar mass polymer Molar mass monomer => Molar mass ethene (C2F4 )= 62.5 Molar mass polyethene = 4760 Substituting 4760 = 77.16 => 77 polychloroethene molecules(whole number) 62.5 The commercial name of polytetrafluorethene(P.T.F.E) is Teflon(P.T.F.E). It is a tough, non-transparent and durable plastic. PVC is used: (i)in making plastic rope (ii)water pipes (iii)crates and boxes 5.Formation of rubber from Latex Natural rubber is obtained from rubber trees. During harvesting an incision is made on the rubber tree to produce a milky white substance called latex. Latex is a mixture of rubber and lots of water. The latex is then added an acid to coagulate the rubber. Natural rubber is a polymer of 2-methylbut-1,3-diene ; H CH3 H H CH2=C (CH3) CH = CH2 H - C = C – C = C - H During natural polymerization to rubber, one double C=C bond break to self add to another molecule.The double bond remaining move to carbon “2” thus; H CH3 H H H CH3 H H - C - C = C - C - C - C = C - C - H H H H Generally the structure of rubber is thus; H CH3 H H -(- C - C = C - C -)n-
113 H H Pure rubber is soft and sticky.It is used to make erasers, car tyres. Most of it is vulcanized.Vulcanization is the process of heating rubber with sulphur to make it harder/tougher.


The latex is then added an acid to coagulate the rubber. Natural rubber is a polymer of 2-methylbut-1,3-diene ; H CH3 H H CH2=C (CH3) CH = CH2 H - C = C – C = C - H During natural polymerization to rubber, one double C=C bond break to self add to another molecule.The double bond remaining move to carbon “2” thus; H CH3 H H H CH3 H H - C - C = C - C - C - C = C - C - H H H H Generally the structure of rubber is thus; H CH3 H H -(- C - C = C - C -)n-
113 H H Pure rubber is soft and sticky.It is used to make erasers, car tyres. Most of it is vulcanized.Vulcanization is the process of heating rubber with sulphur to make it harder/tougher. During vulcanization the sulphur atoms form a cross link between chains of rubber molecules/polymers. This decreases the number of C=C double bonds in the polymer. H CH3 H H H CH3 H H - C - C - C - C - C - C - C - C - H S H H S H H CH3 S H H CH3 S H - C - C - C - C - C - C - C - C - H H H H H H Vulcanized rubber is used to make tyres, shoes and valves. 6.Formation of synthetic rubber Synthetic rubber is able to resist action of oil,abrasion and organic solvents which rubber cannot. Common synthetic rubber is a polymer of 2-chlorobut-1,3-diene ; H Cl H H CH2=C (Cl CH = CH2 H - C = C – C = C - H During polymerization to synthetic rubber, one double C=C bond is broken to self add to another molecule. The double bond remaining move to carbon “2” thus; H Cl H H H Cl H H - C - C = C - C - C - C = C - C - H H H H Generally the structure of rubber is thus; Sulphur atoms make cross link between polymers
114 H Cl H H -(- C - C = C - C -)n- H H Rubber is thus strengthened through vulcanization and manufacture of synthetic rubber.


6.Formation of synthetic rubber Synthetic rubber is able to resist action of oil,abrasion and organic solvents which rubber cannot. Common synthetic rubber is a polymer of 2-chlorobut-1,3-diene ; H Cl H H CH2=C (Cl CH = CH2 H - C = C – C = C - H During polymerization to synthetic rubber, one double C=C bond is broken to self add to another molecule. The double bond remaining move to carbon “2” thus; H Cl H H H Cl H H - C - C = C - C - C - C = C - C - H H H H Generally the structure of rubber is thus; Sulphur atoms make cross link between polymers
114 H Cl H H -(- C - C = C - C -)n- H H Rubber is thus strengthened through vulcanization and manufacture of synthetic rubber. (b)Condensation polymerization Condensation polymerization is the process where two or more small monomers join together to form a larger molecule by elimination/removal of a simple molecule. (usually water). Condensation polymers acquire a different name from the monomers because the two monomers are two different compounds During condensation polymerization: (i)the two monomers are brought together by high pressure to reduce distance between them. (ii)monomers realign themselves at the functional group. (iii)from each functional group an element is removed so as to form simple molecule (of usually H2O/HCl) (iv)the two monomers join without the simple molecule of H2O/HCl Examples of condensation polymerization 1.Formation of Nylon-6,6 Method 1: Nylon-6,6 can be made from the condensation polymerization of hexan1,6-dioic acid with hexan-1,6-diamine.Amines are a group of homologous series with a general formula R-NH2 and thus -NH2 as the functional group. During the formation of Nylon-6,6: (i)the two monomers are brought together by high pressure to reduce distance between them and realign themselves at the functional groups.


(ii)monomers realign themselves at the functional group. (iii)from each functional group an element is removed so as to form simple molecule (of usually H2O/HCl) (iv)the two monomers join without the simple molecule of H2O/HCl Examples of condensation polymerization 1.Formation of Nylon-6,6 Method 1: Nylon-6,6 can be made from the condensation polymerization of hexan1,6-dioic acid with hexan-1,6-diamine.Amines are a group of homologous series with a general formula R-NH2 and thus -NH2 as the functional group. During the formation of Nylon-6,6: (i)the two monomers are brought together by high pressure to reduce distance between them and realign themselves at the functional groups. O O H H H- O - C – (CH2 ) 4 – C – O - H + H –N – (CH2) 6 – N – H
115 (iii)from each functional group an element is removed so as to form a molecule of H2O and the two monomers join at the linkage . O O H H H- O - C – (CH2 ) 4 – C – N – (CH2) 6 – N – H + H 2O . Polymer bond linkage Nylon-6,6 derive its name from the two monomers each with six carbon chain Method 2: Nylon-6,6 can be made from the condensation polymerization of hexan1,6-dioyl dichloride with hexan-1,6-diamine. Hexan-1,6-dioyl dichloride belong to a group of homologous series with a general formula R-OCl and thus -OCl as the functional group. The R-OCl is formed when the “OH” in R-OOH/alkanoic acid is replaced by Cl/chlorine/Halogen During the formation of Nylon-6,6: (i)the two monomers are brought together by high pressure to reduce distance between them and realign themselves at the functional groups.


Polymer bond linkage Nylon-6,6 derive its name from the two monomers each with six carbon chain Method 2: Nylon-6,6 can be made from the condensation polymerization of hexan1,6-dioyl dichloride with hexan-1,6-diamine. Hexan-1,6-dioyl dichloride belong to a group of homologous series with a general formula R-OCl and thus -OCl as the functional group. The R-OCl is formed when the “OH” in R-OOH/alkanoic acid is replaced by Cl/chlorine/Halogen During the formation of Nylon-6,6: (i)the two monomers are brought together by high pressure to reduce distance between them and realign themselves at the functional groups. O O H H Cl - C – (CH2 ) 4 – C – Cl + H –N – (CH2) 6 – N – H (iii)from each functional group an element is removed so as to form a molecule of HCl and the two monomers join at the linkage . O O H H Cl - C – (CH2 ) 4 – C – N – (CH2) 6 – N – H + HCl . Polymer bond linkage The two monomers each has six carbon chain hence the name “nylon-6,6” The commercial name of Nylon-6,6 is Nylon It is a a tough, elastic and durable plastic. It is used to make clothes, plastic ropes and carpets. 2.Formation of Terylene
116 Method 1: Terylene can be made from the condensation polymerization of ethan1,2-diol with benzene-1,4-dicarboxylic acid. Benzene-1,4-dicarboxylic acid a group of homologous series with a general formula R-COOH where R is a ring of six carbon atom called Benzene ring .The functional group is -COOH. During the formation of Terylene: (i)the two monomers are brought together by high pressure to reduce distance between them and realign themselves at the functional groups.


2.Formation of Terylene
116 Method 1: Terylene can be made from the condensation polymerization of ethan1,2-diol with benzene-1,4-dicarboxylic acid. Benzene-1,4-dicarboxylic acid a group of homologous series with a general formula R-COOH where R is a ring of six carbon atom called Benzene ring .The functional group is -COOH. During the formation of Terylene: (i)the two monomers are brought together by high pressure to reduce distance between them and realign themselves at the functional groups. O O H- O - C – C6H5 – C – O - H + H –O – CH2 CH2 – O – H (iii)from each functional group an element is removed so as to form a molecule of H2O and the two monomers join at the linkage . O O H- O - C – C6H5 – C – O – (CH2) 6 – N – H + H 2O . Polymer bond linkage of terylene
117 Method 2: Terylene can be made from the condensation polymerization of benzene-1,4-dioyl dichloride with ethan-1,2-diol. Benzene-1,4-dioyl dichloride belong to a group of homologous series with a general formula R-OCl and thus -OCl as the functional group and R as a benzene ring. The R-OCl is formed when the “OH” in R-OOH is replaced by Cl/chlorine/Halogen During the formation of Terylene (i)the two monomers are brought together by high pressure to reduce distance between them and realign themselves at the functional groups. O O Cl - C – C5H5 – C – Cl + H –O – CH2 CH2 – O - H (iii)from each functional group an element is removed so as to form a molecule of HCl and the two monomers join at the linkage . O O Cl - C – C5H5 – C – O – CH2 CH2 – O – H + HCl . Polymer bond linkage of terylene
118 The commercial name of terylene is Polyester /polyster It is a a tough, elastic and durable plastic.


O O Cl - C – C5H5 – C – Cl + H –O – CH2 CH2 – O - H (iii)from each functional group an element is removed so as to form a molecule of HCl and the two monomers join at the linkage . O O Cl - C – C5H5 – C – O – CH2 CH2 – O – H + HCl . Polymer bond linkage of terylene
118 The commercial name of terylene is Polyester /polyster It is a a tough, elastic and durable plastic. It is used to make clothes, plastic ropes and sails and plastic model kits. 119 Practice questions Organic chemistry 1. A student mixed equal volumes of Ethanol and butanoic acid. He added a few drops of concentrated Sulphuric (VI) acid and warmed the mixture (i) Name and write the formula of the main products Name…………………………………. Formula…………………………………….. (ii) Which homologous series does the product named in (i) above belong? 2. The structure of the monomer phenyl ethene is given below:- a) Give the structure of the polymer formed when four of the monomers are added together b) Give the name of the polymer formed in (a) above 3. Explain the environmental effects of burning plastics in air as a disposal method 4. Write chemical equation to represent the effect of heat on ammonium carbonate 5. Sodium octadecanoate has a chemical formula CH3(CH2)6 COO-Na+, which is used as soap. HC = CH2 O
120 Explain why a lot of soap is needed when washing with hard water 6. A natural polymer is made up of the monomer: (a) Write the structural formula of the repeat unit of the polymer (b) When 5.0 x 10-5 moles of the polymer were hydrolysed, 0.515g of the monomer were obtained. Determine the number of the monomer molecules in this polymer. (C = 12; H = 1; N = 14; O =16) 7. The formula below represents active ingredients of two cleansing agents A and B O CH3CH2CH C OH
121 Which one of the cleansing agents would be suitable to be used in water containing magnesium hydrogen carbonate? Explain
122 8.


(C = 12; H = 1; N = 14; O =16) 7. The formula below represents active ingredients of two cleansing agents A and B O CH3CH2CH C OH
121 Which one of the cleansing agents would be suitable to be used in water containing magnesium hydrogen carbonate? Explain
122 8. Study the polymer below and use it to answer the questions that follow: (a) Give the name of the monomer and draw its structures (b) Identify the type of polymerization that takes place (c) State one advantage of synthetic polymers 9. Ethanol and Pentane are miscible liquids. Explain how water can be used to separate a mixture of ethanol and pentane 10. (a) What is absolute ethanol? GLUCOSE SOLUTION CRUDE ETHANOL 95% ETHANOL ABSOLUTE ETHANOL G H H H H H C C C C
123 (b) State two conditions required for process G to take place efficiently 11. (a) (i) The table below shows the volume of oxygen obtained per unit time when hydrogen peroxide was decomposed in the presence of manganese (IV) Oxide. Use it to answer the questions that follow:- Time in seconds Volume of Oxygen evolved (cm3) 0 30 60 90 120 150 180 210 240 270 300 0 10 19 27 34 38 43 45 45 45 45 (i) Plot a graph of volume of oxygen gas against time
124 (ii) Determine the rate of reaction at time 156 seconds (iii) From the graph, find the time taken for 18cm3 of oxygen to be produced (iv) Write a chemical equation to show how hydrogen peroxide decomposes in the presence of manganese (IV) Oxide (b) The diagram below shows how a Le’clanche (Dry cell) appears:- (i) What is the function of MnO2 in the cell above? (ii) Write the equation of a reaction that occurs at the cathode
125 (iii) Calculate the mass of Zinc that is consumed when a current of 0.1amperes flows through the above cell for 30minutes (1F =96500c Zn =65) 12.