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5682bf2e-6055-4b76-b576-97a1edcdcc28
# ANATOMY OF FLOWERING PLANTS # CHAPTER 6 # 6.1 The Tissue System You can very easily see the structural similarities and variations in the external morphology of the larger living organism, both plants and animals. Similarly, if we were to study the internal structure, one also finds several similarities as well as...
0
11
Biology
06
3a2958c7-de76-4f2f-9517-69f30901e718
# BIOLOGY arranged cells, which form a continuous layer. Epidermis is usually single-layered. Epidermal cells are parenchymatous with a small amount of cytoplasm lining the cell wall and a large vacuole. The outside of the epidermis is often covered with a waxy thick layer called the cuticle which prevents the loss of...
1
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Biology
06
c06d56d6-f476-4561-a69d-26c9150127ca
# ANATOMY OF FLOWERING PLANTS # 6.1.3 The Vascular Tissue System The vascular system consists of complex tissues, the phloem and the xylem. The xylem and phloem together constitute vascular bundles (Figure 6.2). In dicotyledonous stems, cambium is present between phloem and xylem. Such vascular bundles because of the...
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Biology
06
5d35dcb8-9f1b-43b6-ab2c-90f7a9f7c8e1
# 74 # BIOLOGY with intercellular spaces. The innermost layer of the cortex is called endodermis. It comprises a single layer of barrel-shaped cells without any intercellular spaces. The tangential as well as radial walls of the endodermal cells have a deposition of water-impermeable, waxy material suberin in the for...
3
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Biology
06
3ef1b079-bfe3-431b-a457-40442f049504
# ANATOMY OF FLOWERING PLANTS (Figure 6.4 a). Covered with a thin layer of cuticle, it may bear trichomes and a few stomata. The cells arranged in multiple layers between epidermis and pericycle constitute the cortex. It consists of three sub-zones. The outer hypodermis consists of a few layers of collenchymatous cell...
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Biology
06
adfae95d-8ebf-4057-a3fe-a50ca5b3f059
# 76 # BIOLOGY present on the inner side of the endodermis and above the phloem in the form of semi-lunar patches of sclerenchyma. In between the vascular bundles there are a few layers of radially placed parenchymatous cells, which constitute medullary rays. A large number of vascular bundles are arranged in a ring;...
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Biology
06
04dade93-54f7-4eda-9db0-16eb6cac54b4
# ANATOMY OF FLOWERING PLANTS vertically and parallel to each other. The oval or spongy parenchyma is situated below the palisade cells and extends to the lower epidermis. There are numerous large spaces and air cavities between these cells. The vascular system includes vascular bundles, which can be seen in the veins...
6
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Biology
06
f9a2f85c-e719-4b49-84b7-81d93f21f4b3
# BIOLOGY # EXERCISES 1. Draw illustrations to bring out the anatomical difference between - (a) Monocot root and Dicot root - (b) Monocot stem and Dicot stem 2. Cut a transverse section of young stem of a plant from your school garden and observe it under the microscope. How would you ascertain whether it is a monoc...
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Biology
06
0d2a54cc-7d75-46ee-b718-877a09a35eff
# CHAPTER 17 # LOCOMOTION AND MOVEMENT # 17.1 Types of Movement Movement is one of the significant features of living beings. Animals and plants exhibit a wide range of movements. Streaming of protoplasm in the unicellular organisms like Amoeba is a simple form of movement. Movement of cilia, flagella and tentacles ...
0
11
Biology
17
1a57d946-30b7-4cd9-a2ca-a5108623024d
# BIOLOGY Some specialised cells in our body like macrophages and leucocytes in blood exhibit amoeboid movement. It is effected by pseudopodia formed by the streaming of protoplasm (as in Amoeba). Cytoskeletal elements like microfilaments are also involved in amoeboid movement. Ciliary movement occurs in most of our ...
1
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Biology
17
32cbfa28-4212-4297-b690-bc956cc2620a
# LOCOMOTION AND MOVEMENT As the name suggests, Cardiac muscles are the muscles of heart. Many cardiac muscle cells assemble in a branching pattern to form a cardiac muscle. Based on appearance, cardiac muscles are striated. They are involuntary in nature as the nervous system does not control their activities directl...
2
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Biology
17
4313b38d-eca3-4002-8481-822b1867222f
# 220 # BIOLOGY myosin. Both the proteins are arranged as rod-like structures, parallel to each other and also to the longitudinal axis of the myofibrils. Actin filaments are thinner as compared to the myosin filaments, hence are commonly called thin and thick filaments respectively. In the centre of each ‘I’ band is...
3
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Biology
17
f27b9de1-dba2-4669-975f-c190b9872ce4
# LOCOMOTION AND MOVEMENT # 17.2.1 Structure of Contractile Proteins Each actin (thin) filament is made of two ‘F’ (filamentous) actins helically wound to each other. Each ‘F’ actin is a polymer of monomeric ‘G’ (Globular) actins. Two filaments of another protein, tropomyosin also run close to the ‘F’ actins througho...
4
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Biology
17
e762b418-2b19-4985-89c9-05774d8055bc
# BIOLOGY Muscle contraction is initiated by a signal sent by the central nervous system (CNS) via a motor neuron. A motor neuron along with the muscle fibres connected to it constitute a motor unit. The junction between a motor neuron and the sarcolemma of the muscle fibre is called the neuromuscular junction or moto...
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Biology
17
b2bebe10-fc48-49ba-8839-42c2e47adb93
# LOCOMOTION AND MOVEMENT # 223 # Figure 17.5 Sliding-filament theory of muscle contraction (movement of the thin filaments and the relative size of the I band and H zones) and breakage is repeated causing further sliding. The process continues till the Ca++ ions are pumped back to the sarcoplasmic cisternae result...
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Biology
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1a2c95b2-05aa-4fd4-93b6-5a1d3b90c0a5
# 17.3 SKELETAL SYSTEM Skeletal system consists of a framework of bones and a few cartilages. This system has a significant role in movement shown by the body. Imagine chewing food without jaw bones and walking around without the limb bones. Bone and cartilage are specialised connective tissues. The former has a very ...
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Biology
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2c0a36a7-b9d5-4bbb-815e-59810eabb8d4
# LOCOMOTION AND MOVEMENT # 225 Our vertebral column (Figure 17.7) is formed by 26 serially arranged units called vertebrae and is dorsally placed. It extends from the base of the skull and constitutes the main framework of the trunk. Each vertebra has a central hollow portion (neural canal) through which the spinal ...
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Biology
17
1f8fd354-59db-4fa1-98e1-26f2a757ac31
# BIOLOGY # 17.4 JOINTS Joints are essential for all types of movements involving the bony parts of the body. Locomotory movements are no exception to this. # Figure 17.9 Right pectoral girdle and upper arm. (frontal view) Humerus, radius and ulna, carpals (wrist bones – 8 in number), metacarpals (palm bones – 5 i...
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Biology
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d0a6f37f-4ce4-4f2a-837d-0a4e24daff6c
# LOCOMOTION AND MOVEMENT This. Joints are points of contact between bones, or between bones and cartilages. Force generated by the muscles is used to carry out movement through joints, where the joint acts as a fulcrum. The movability at these joints vary depending on different factors. Joints have been classified in...
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Biology
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a581edc2-60cb-4c21-9102-b8e60d2aa1f0
# BIOLOGY called locomotion. Animals move generally in search of food, shelter, mate, breeding ground, better climate or to protect themselves. The cells of the human body exhibit amoeboid, ciliary and muscular movements. Locomotion and many other movements require coordinated muscular activities. Three types of musc...
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Biology
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16a88be0-d2f6-4378-b063-d3dff595f4e6
# LOCOMOTION AND MOVEMENT # 229 # 4. Write true or false. If false change the statement so that it is true. - (a) Actin is present in thin filament - (b) H-zone of striated muscle fibre represents both thick and thin filaments. - (c) Human skeleton has 206 bones. - (d) There are 11 pairs of ribs in man. - (e) Sternu...
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Biology
17
45db6140-00aa-4639-8a5f-61c54adfe10f
# CHAPTER 12 # RESPIRATION IN PLANTS # 12.1 Do Plants Breathe? All of us breathe to live, but why is breathing so essential to life? What happens when we breathe? Also, do all living organisms, including plants and microbes, breathe? If so, how? # 12.2 Glycolysis All living organisms need energy for carrying out d...
0
11
Biology
12
a97767ed-4b67-4567-8a1c-c692c23395e5
# BIOLOGY directly (herbivores) or indirectly (carnivores). Saprophytes like fungi are dependent on dead and decaying matter. What is important to recognise is that ultimately all the food that is respired for life processes comes from photosynthesis. This chapter deals with cellular respiration or the mechanism of br...
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Biology
12
715a6db5-dd59-48b9-8f7d-425149c9c848
# RESPIRATION IN PLANTS The distance that gases must diffuse even in large, bulky plants is not great. Each living cell in a plant is located quite close to the surface of the plant. ‘This is true for leaves’, you may ask, ‘but what about thick, woody stems and roots?’ In stems, the ‘living’ cells are organised in thi...
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Biology
12
0a439953-e9b4-4d28-a8e7-8572839f49b1
# 156 # BIOLOGY |Glucose|ATP (6C)|ADP|Glucose-6-phosphate (6C)| |---|---|---|---| |Fructose-6-phosphate|ATP (6C)|ADP|Fructose 1, 6-bisphosphate (6C)| |Triose phosphate|Triose phosphate|(glyceraldehyde-3-phosphate)|(Dihydroxy acetone phosphate)| |NAD+| |NADH+H+| | |2 × Triose bisphosphate|(1,3 bisphosphoglyceric acid)...
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Biology
12
b39eb309-d3dc-4cd7-9e5b-01de0d96d2f1
# RESPIRATION IN PLANTS There are three major ways in which different cells handle pyruvic acid produced by glycolysis. These are lactic acid fermentation, alcoholic fermentation and aerobic respiration. Fermentation takes place under anaerobic conditions in many prokaryotes and unicellular eukaryotes. For the complet...
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Biology
12
d6611084-928c-4218-a257-a38175d83ae5
# BIOLOGY synthesise a larger number of ATP molecules needed for cellular metabolism? In eukaryotes these steps take place within the mitochondria and this requires O. Aerobic respiration is the process that leads to a complete oxidation of organic substances in the presence of oxygen, and releases CO2, water and a la...
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Biology
12
8e8f6b82-292b-49c3-a48d-860f1860d006
# RESPIRATION IN PLANTS and then succinyl-CoA. In the remaining steps of citric acid cycle, succinyl-CoA is oxidised to Pyruvate (3C) allowing the cycle to continue. During the conversion of succinyl-CoA to succinic acid a molecule of GTP is synthesised. This is a substrate level phosphorylation. In a coupled reaction...
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Biology
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c8546d49-f969-4f6d-8be7-5ae875e27ffc
# BIOLOGY produced in the mitochondrial matrix during citric acid cycle are oxidised by an NADH dehydrogenase (complex I), and electrons are then transferred to ubiquinone located within the inner membrane. Ubiquinone also receives reducing equivalents via FADH (complex II) that is generated during oxidation of succin...
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Biology
12
0c3acc69-29f3-4d2b-8617-c862cc763273
# RESPIRATION IN PLANTS transport system is utilised in synthesising ATP with the help of ATP synthase (complex V). This complex consists of two major components, F1 and F0 (Figure 12.5). The F1 headpiece is a peripheral membrane protein complex and contains the site for synthesis of ATP from ADP and inorganic phospha...
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Biology
12
bb5cd83d-92a6-4e4e-9f9c-3bc1fdc6f0e9
# 12.6 AMPHIBOLIC PATHWAY Glucose is the favoured substrate for respiration. All carbohydrates are usually first converted into glucose before they are used for respiration. Other substrates can also be respired, as has been mentioned earlier then they do not enter the respiratory pathway at the first step. See Figure...
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Biology
12
c1f4fe03-c609-4288-8a3b-5bad526d57cc
# RESPIRATION IN PLANTS # 12.7 RESPIRATORY QUOTIENT Let us now look at another aspect of respiration. As you know, during aerobic respiration, O2 is consumed and CO2 is released. The ratio of the volume of CO2 evolved to the volume of O2 consumed in respiration is called the respiratory quotient (RQ) or respiratory r...
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Biology
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908b8218-c5c8-421f-aca9-b26f2baa9107
# BIOLOGY C6H12 + 6O2 ⟶ 6CO2 + 6H2O + Energy RQ = 6CO2 / 6O2 = 1.0 When fats are used in respiration, the RQ is less than 1. Calculations for a fatty acid, tripalmitin, if used as a substrate is shown: 2(C51H98O6) + 145O2 ⟶ 102CO2 + 98H2O + Energy Tripalmitin RQ = 102CO2 / 145O2 = 0.7 When proteins are respirato...
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Biology
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aa2c9f1f-61a0-4c91-9add-2109f9980910
# RESPIRATION IN PLANTS system of electron carriers called electron transport system (ETS) located on the inner membrane of the mitochondria. The electrons, as they move through the system, release enough energy that are trapped to synthesise ATP. This is called oxidative phosphorylation. In this process O2 is the ult...
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Biology
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0b9fa7d2-212a-4e7b-bbcb-ff8d6d96a29e
# Unit 3 # Classification of Elements and Periodicity in Properties The Periodic Table is arguably the most important concept in chemistry, both in principle and in practice. It is the everyday support for students, it suggests new avenues of research to professionals, and it provides a succinct organization of the w...
0
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Chemistry
103
a8c5fe37-053a-4e7e-ba3f-152f9c1e6c72
# 3.2 Genesis of Periodic Classification The classification of elements into groups and development of Periodic Law and Periodic Table are the consequences of systematising the knowledge gained by a number of scientists through their observations and experiments. The German chemist, Johann Dobereiner in early 1800’s w...
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Chemistry
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b236068b-02f4-42fe-a988-e79bd8c6b95e
# Chemistry a periodically repeated pattern. Unlike classification if the order of atomic weight was strictly followed. He ignored the order of atomic weights, thinking that the atomic measurements might be incorrect, and placed the elements with similar properties together. For example, iodine with lower atomic weigh...
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Chemistry
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3e11aa85-2be2-467f-8440-eb312ead9ca7
# CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES # SERIES AND GROUPS IN THE PERIODIC SYSTEM OF ELEMENTS # 2024-25 Fig. 3.1 Mendeleev’s Periodic Table published earlier 77
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Chemistry
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14a2607e-069a-408e-8a41-13ce3c4bcfb4
# Chemistry # 3.3 Modern Periodic Law and the Physical and Chemical Properties of Elements We must bear in mind that when Mendeleev developed his Periodic table, chemists knew nothing about the internal structure of atom. However, the beginning of the 20th century witnessed profound developments in theories about sub...
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Chemistry
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84da2dfb-4d27-4be2-9f8b-3f1193de89fd
# CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES IA IIA III A IV A V A VI A VII A VIII IB IIB III B IV B V B VI B VII B 2024-25 Fig. 3.2 Long form of the Periodic Table of the Elements with their atomic numbers and ground state outer electronic configurations. The groups are numbered 1-18 in accordance with...
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Chemistry
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a8ddd5d7-81b6-4544-b769-117e266bc680
# Chemistry a few atoms of them are obtained. Their synthesis and characterisation, therefore, require highly sophisticated costly equipment and laboratory. Such work is carried out with competitive spirit only in some laboratories in the world. Scientists, before collecting the reliable data on the new element, at ti...
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Chemistry
103
69b73dd4-510a-45eb-9d48-42e5ac35502b
# CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES Thus, the new element first gets a temporary name, with symbol consisting of three letters. Later permanent name and symbol are given by a vote of IUPAC representatives from each country. The permanent name might reflect the country (or state of the country) i...
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Chemistry
103
2a6b0933-7259-4b0f-bb2a-2f401c247e6d
# Chemistry Actinium (Z = 89) gives the 5f-inner transition series known as the actinoid series. The 4f- and 5f-inner transition series of elements are placed separately in the Periodic Table to maintain its structure and to preserve the principle of classification by keeping elements with similar properties in a sing...
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Chemistry
103
215ed1d3-d125-4d19-b688-44150cb681e6
# CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PRO # Og # PE # TI # Mc # Nh # 2024-25 # Fig. 3.3 The types of elements in the Periodic Table based on the orbitals that are being filled. Also shown is the broad division of elements into METALS, METALLOIDS, and NON-METALS. 83
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Chemistry
103
6b7694a9-1608-40c1-8a77-dd30f1e6420a
# Chemistry Reactive metals with low ionization enthalpies. They lose the outermost electron(s) readily to form 1+ ion (in the case of alkali metals) or 2+ ion (in the case of alkaline earth metals). The metallic character and the reactivity increase as we go down the group. Because of high reactivity they are never f...
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Chemistry
103
e52084df-7a0a-484c-a9b1-ebffad90e062
# CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES # 3.6.5 metals, non-metals and metalloids In addition to displaying the classification of elements into s-, p-, d-, and f-blocks, Fig. 3.3 shows another broad classification of elements based on their properties. The elements can be divided into metals and no...
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Chemistry
103
cc788afc-1d2c-4fdc-beaf-adc56c7059a6
# Chemistry Small. Secondly, since the electron cloud surrounding the atom does not have a sharp boundary, the determination of the atomic size cannot be precise. In other words, there is no practical way by which the size of an individual atom can be measured. However, an estimate of the atomic size can be made by kn...
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Chemistry
103
cee243b5-76c9-41e3-b3e4-63aece0cc1b1
# CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES # 87 Fig. 3.4 (a) Variation of atomic radius with atomic number across the second period Fig. 3.4 (b) Variation of atomic radius with atomic number for alkali metals and halogens # (b) Ionic Radius The removal of an electron from an atom results in the for...
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Chemistry
103
f953bdc6-d473-4922-84c5-03aa77ae0ba0
# Chemistry In other words, the first ionization enthalpy for an element X is the enthalpy change (∆i H) for the reaction depicted in equation 3.1. X(g) → X⁺(g) + e– (3.1) The ionization enthalpy is expressed in units of kJ mol–1. We can define the second ionization enthalpy as the energy required to remove the seco...
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Chemistry
103
3d06863c-10ae-4b77-9b09-7cad608bff8e
# CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES valence electron in an atom will be less than the 2s electrons of beryllium. Therefore, it is the actual charge on the nucleus because of “shielding” or “screening” of the valence electron from the nucleus by the intervening core electrons. For example, the 2s...
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Chemistry
103
cf73fd94-bae5-42d7-9026-102885f19172
# Chemistry # Table 3.7 Electron Gain Enthalpies* / (kJ mol–1) of some main Group Elements |Group 1|∆egH|Group 16|∆egH|Group 17|∆egH|Group 0|∆egH| |---|---|---|---|---|---|---|---| |H|– 73|O|– 141|F|– 328|He|+ 48| |Li|– 60|S|– 200|Cl|– 349|Ne|+ 116| |Na|– 53|Se|– 195|Br|– 325|Ar|+ 96| |K|– 48|Te|– 190|I|– 295|Kr|+ 96...
16
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Chemistry
103
9406c08d-1173-45ac-bda2-07a09ec3e5d9
# CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES Ability to attract electrons. Approximate values for the electronegativity of a few elements are given in Table 3.8(a). The electronegativity of any given element is not constant; it varies depending on the element to which it is bound. Though it is not a meas...
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Chemistry
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b95b4dad-1c8a-4faa-ba72-7c218c51a620
# CHEMISTRY to gain electrons. Therefore, electronegativity is directly related to that non-metallic properties of elements. It can be further extended to say that the electronegativity is inversely related to the metallic properties of elements. Thus, the increase in electronegativities across a period is accompanied...
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Chemistry
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56725e40-dd55-4755-91aa-1c45e1696b26
# CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES # Table 3.9 # Periodic trends in Valence of Elements as shown by the formulas of their Compounds |Group|1|2|13|14|15|16|17| |---|---|---|---|---|---|---|---| |Formula of hydride|LiH|CaH₂|B₂H₆|CH₄|NH₃|H₂O|HF| | |NaH| |AlH₃|SiH₄|PH₃|H₂S|HCl| | |KH| | |GeH₄|AsH...
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Chemistry
103
b53fdc86-a5ab-4c46-8185-4af562cf95a0
# Chemistry # Problem 3.9 Are the oxidation state and covalency of Al in [AlCl(H₂O)₅]²⁺ same? Solution: No. The oxidation state of Al is +3 and the covalency is 6. # 3.7.3 Periodic trends and Chemical reactivity We have observed the periodic trends in certain fundamental properties such as atomic and ionic radii, ...
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Chemistry
103
26315f36-1c20-42c4-905f-b224b97e57b4
# CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES In a group, the increase in atomic and ionic radii with increase in atomic number generally results in a gradual decrease in ionization enthalpies and a regular decrease (with exception in some third period elements as shown in section 3.7.1(d)) in electron ga...
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Chemistry
103
886472f4-f927-416b-abaf-8af2492b6276
# Chemistry # Exercises 1. What is the basic theme of organisation in the periodic table? 2. Which important property did Mendeleev use to classify the elements in his periodic table and did he stick to that? 3. What is the basic difference in approach between the Mendeleev’s Periodic Law and the Modern Periodic Law?...
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Chemistry
103
725a56df-2518-4e54-b308-cc45dcce995b
# CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES # 3.17 How would you explain the fact that the first ionization enthalpy of sodium is lower than that of magnesium but its second ionization enthalpy is higher than that of magnesium? # 3.18 What are the various factors due to which the ionization enthalpy ...
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Chemistry
103
9957c264-94b3-47a8-936a-a78dcd1399a2
# Chemistry # 3.31 The first (∆iH₁) and the second (∆iH₂) ionization enthalpies (in kJ mol–1) and the (∆egH) electron gain enthalpy (in kJ mol–1) of a few elements are given below: |Elements|∆H₁|∆H₂|∆egH| |---|---|---|---| |I|520|7300|–60| |II|419|3051|–48| |III|1681|3374|–328| |IV|1008|1846|–295| |V|2372|5251|+48| ...
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Chemistry
103
03d2b89c-ac6a-4a2a-b769-d6283de6ddba
# CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES 3.35 Anything that influences the valence electrons will affect the chemistry of the element. Which one of the following factors does not affect the valence shell? - (a) Valence principal quantum number (n) - (b) Nuclear charge (Z) - (c) Nuclear mass - (d) Nu...
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Chemistry
103
e4495b16-cb37-412e-bc0b-7d48f82c03b4
# UNIT 1 # T1082CHOT # SOME BASIC CONCEPTS OF CHEMISTRY Chemistry is the science of molecules and their transformations. It is the science not so much of the one hundred elements but of the infinite variety of molecules that may be built from them. After studying this unit, you will be able to: - appreciate the co...
0
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Chemistry
101
0e99ba4c-4e87-43f0-b673-470843db8e1e
# Chemistry Other cultures – especially the Chinese and the Indian – had their own alchemical traditions. These included much knowledge of chemical processes and techniques. In ancient India, chemistry was called Rasayan Shastra, Rastantra, Ras Kriya or Rasvidya. It included metallurgy, medicine, manufacture of cosmet...
1
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Chemistry
101
938625d2-5ca1-4d2a-978f-cbab3f2f245a
# SOME BASIC CONCEPTS OF CHEMISTRY A number of classical texts, like Atharvaveda (1000 BCE) mention some dye stuff, the material used were turmeric, madder, sunflower, orpiment, cochineal and lac. Some other substances having tinting property were kamplcica, pattanga and jatuka. Varähmihir’s Brihat Samhita references...
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Chemistry
101
c66d2148-b145-46e4-8174-fdd019491936
# 1.1 Importance of Chemistry Chemistry plays a central role in science and is often intertwined with other branches of science. Principles of chemistry are applicable in diverse areas, such as weather patterns, functioning of brain and operation of a computer, production in chemical industries, manufacturing fertilis...
3
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Chemistry
101
87fe79cf-5999-40ff-889e-7bbccda23744
# SOME BASIC CONCEPTS OF CHEMISTRY Fig. 1.1 Arrangement of particles in solid, liquid and gaseous state (iii) Gases have neither definite volume nor definite shape. They completely occupy the space in the container in which they are placed. These three states of matter are interconvertible by changing the conditions...
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Chemistry
101
8c353c87-ff29-4331-b312-a4b6304d50f7
# Chemistry and molecules from the previous classes; however, you will be studying about them in detail in Unit 2. Sodium, copper, silver, hydrogen, oxygen, etc., are some examples of elements. Their all atoms are of one type. However, the atoms of different elements are different in nature. Some elements, such as sod...
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Chemistry
101
6ab3fb4a-6b4f-4d1a-8fae-6eebbbed9d2d
# SOME BASIC CONCEPTS OF CHEMISTRY will learn about the measurement of physical properties. # 1.3.2 measurement of physical properties Quantitative measurement of properties is required for scientific investigation. Many properties of matter, such as length, area, volume, etc., are quantitative in nature. Any quanti...
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Chemistry
101
08523ec7-1688-4763-a465-d86bb4d00515
# Chemistry The definitions of the SI base units are given in Table 1.2. The SI system allows the use of prefixes to indicate the multiples or submultiples of a unit. These prefixes are listed in Table 1.3. Let us now quickly go through some of the quantities which you will be often using in this book. |Unit|Symbol|D...
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Chemistry
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9a414b15-ff61-4b86-a12f-a17445497d3c
# Some Basic Concepts of Chemistry # Table 1.3 Prefixes used in the SI System |multiple|Prefix|Symbol| |---|---|---| |10–24|yocto|y| |10–21|zepto|z| |10–18|atto|a| |10–15|femto|f| |10–12|pico|p| |10–9|nano|n| |10–6|micro|μ| |10–3|milli|m| |10–2|centi|c| |10–1|deci|d| |10|deca|da| |102|hecto|h| |103|kilo|k| |106|mega|...
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Chemistry
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59428f4b-eed7-4e16-a098-daeb495c52a5
# Chemistry In the laboratory, the volume of liquids or solutions can be measured by graduated cylinder, burette, pipette, etc. A volumetric flask is used to prepare a known volume of a solution. These measuring devices are shown in Fig. 1.7. Generally, the thermometer with Celsius scale are calibrated from 0° to 100...
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Chemistry
101
a4824e23-890b-4254-a9cd-776d1e98ee5d
# SOME BASIC CONCEPTS OF CHEMISTRY After defining a unit of measurement such as the kilogram or the metre, scientists agreed on reference standards that make it possible to calibrate all measuring devices. For getting reliable measurements, all devices such as metre sticks and analytical balances have been calibrated ...
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Chemistry
101
95455141-34ba-4654-a51b-32cb3b2bcf33
# Chemistry # Multiplication and Division These two operations follow the same rules which are there for exponential numbers, i.e. (5.6 × 105) × (8 × 106) = (5.6 × 8) × 105+6 = 38.4 × 1011 = 3.84 × 1012 (9.8 × 10-2) × (2.5 × 10-6) = (9.8 × 2.5) × 10-2-6 = 24.50 × 10-8 = 2.450 × 10-7 (2.7 × 10-3) ÷ (5.5 × 10-4) =...
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Chemistry
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88c800b7-d5ad-44c2-860d-b7f905e27e39
# SOME BASIC CONCEPTS OF CHEMISTRY # Counting the numbers of object For example, 2 balls or 20 eggs, have infinite significant figures as these are exact numbers and can be represented by writing infinite number of zeros after placing a decimal i.e., 2 = 2.000000 or 20 = 20.000000. In numbers written in scientific n...
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Chemistry
101
f1623fc7-0464-43ce-bf29-c7256004bd5b
# Chemistry # Solution The above is multiplied by the unit factor. We know that 1 in = 2.54 cm. From this equivalence, we can write: 1 in 2.54 2.54 = 1 = . cm . cm = 1 in Thus, 1 in equals 1 and .1 cm. Both of these are called unit factors. If some number is multiplied by these unit factors (i.e., 1), it will no...
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Chemistry
101
2f765b87-2e43-4bd8-9c0d-53cf2ec6d55a
# SOME BASIC CONCEPTS OF CHEMISTRY # 1.5.2 Law of Definite Proportions This law was given by a French chemist, Joseph Proust. He stated that a given compound always contains exactly the same proportion of elements by weight. Proust worked with two samples of cupric carbonate — one of which was of natural origin and t...
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Chemistry
101
70312553-3fa7-43b4-8ed6-2921e5f80fa8
# CHEMISTRY Fig. 1.9 Two volumes of hydrogen react with one volume of oxygen to give two volumes of water vapour cannot combine and molecules of oxygen or hydrogen containing two atoms did not exist. Dalton’s theory could explain the laws of chemical combination. However, it could not explain the laws of gaseous volu...
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Chemistry
101
350f8021-fc98-4f57-8bee-9c2b6ea4dff5
# SOME BASIC CONCEPTS OF CHEMISTRY # 1.7.3 molecular mass Mass of an atom of hydrogen = 1.6736×10–24g Thus, in terms of amu, the mass of hydrogen atom = 1.0078 amu = 1.0080 amu Similarly, the mass of oxygen - 16 (¹⁶O) atom would be 15.995 amu. ‘u’ At present, ‘amu’ has been replaced by *u*, which is known as unifi...
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Chemistry
101
f208de6f-40c2-49a0-bd81-17584189510a
# Chemistry Thus, the formula mass of sodium chloride is atomic mass of sodium + atomic mass of chlorine = 23.0 u + 35.5 u = 58.5 u # Problem 1.1 Calculate the molecular mass of glucose (C6H12O6) molecule. # Solution Molecular mass of glucose (C6H12O6) = 6 (12.011 u) + 12 (1.008 u) + 6 (16.00 u) = (72.066 u) +...
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Chemistry
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7b8503f9-3e8d-40ee-8236-ff86af97e572
# Some Basic Concepts of Chemistry # 1.9.1 Empirical Formula for Molecular Formula You would ask is: what is its formula or what are its constituents and in what ratio are they present in the given compound? For known compounds also, such information provides a check whether the given sample contains the same percent...
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Chemistry
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2b6b8381-3d45-42bc-8482-2f696995fb61
# Chemistry Step 3. Divide each of the mole values obtained above by the smallest number amongst them. Since 2.021 is the smallest value, division by it gives a ratio of 2:1:1 for H:C:Cl. In case the ratios are not whole numbers, then they may be converted into whole numbers by multiplying by the suitable coefficient...
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Chemistry
101
b17f2bd1-9bad-4042-8490-c86736828927
# SOME BASIC CONCEPTS OF CHEMISTRY reactant which is present in the least amount gets consumed after sometime and after that further reaction does not take place whatever be the amount of the other reactant. Hence, the reactant, which gets consumed first, limits the amount of product formed and is, therefore, called t...
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Chemistry
101
86c566c3-182c-4cc7-89d1-d6520ec68a58
# Problem 1.3 Calculate the amount of water (g) produced by the combustion of 16 g of methane. # Solution The balanced equation for the combustion of methane is: CH₄ (g) + 2O₂(g) → CO₂ (g) + 2H₂O (g) 1. 16 g of CH₄ corresponds to one mole. 2. From the above equation, 1 mol of CH₄ (g) gives 2 mol of H₂O (g). 2 mol...
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Chemistry
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26551991-90ea-42b1-a70a-a45d1f509353
# SOME BASIC CONCEPTS OF CHEMISTRY # 3. Molarity It is the most widely used unit and is denoted by M. It is defined as the number of moles of the solute in 1 litre of the solution. Thus, Molarity (M) = No. of moles of solute / Volume of solution in litres Suppose, we have 1 M solution of a substance, say NaOH, and ...
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Chemistry
101
229bb647-f3e7-471e-8818-93e6a31986ed
# CHEMISTRY # Problem 1.7 Calculate the molarity of NaOH in the solution prepared by dissolving its 4 g in enough water to form 250 mL of the solution. # Solution Since molarity (M) |Mass of NaCl in 1 L solution|= 3 × 58.5 = 175.5 g| |---|---| |Mass of 1L solution|= 1000 × 1.25 = 1250 g (since density = 1.25 g mL–...
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Chemistry
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f381b36d-ebd4-4b80-b5a8-209f2a5a004c
# SOME BASIC CONCEPTS OF CHEMISTRY and the Metric Systems are widely used. The scientific community, however, has agreed to have a uniform and common system throughout the world, which is abbreviated as SI units (International System of Units). Since measurements involve recording of data, which are always associated...
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Chemistry
101
c41c06a7-8838-4bbb-9910-b93051eeccd3
# Chemistry # 1.6 Calculate the concentration of nitric acid in moles per litre in a sample which has a density, 1.41 g mL–1 and the mass per cent of nitric acid in it being 69%. # 1.7 How much copper can be obtained from 100 g of copper sulphate (CuSO4)? # 1.8 Determine the molecular formula of an oxide of iron,...
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Chemistry
101
edab70c6-ff9f-4b21-a66a-e59d9220d18f
# SOME BASIC CONCEPTS OF CHEMISTRY # 1.20 Round up the following upto three significant figures: - (i) 34.216 - (ii) 10.4107 - (iii) 0.04597 - (iv) 2808 # 1.21 The following data are obtained when dinitrogen and dioxygen react together to form different compounds: |mass of dinitrogen|mass of dioxygen| |---|---| |...
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Chemistry
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0c83c7a2-ca33-435c-beab-eaeffc48db4d
# CHEMISTRY # 1.28 Which one of the following will have the largest number of atoms? - (i) 1 g Au (s) - (ii) 1 g Na (s) - (iii) 1 g Li (s) - (iv) 1 g of Cl₂(g) # 1.29 Calculate the molarity of a solution of ethanol in water, in which the mole fraction of ethanol is 0.040 (assume the density of water to be one). #...
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Chemistry
101
2aeb6c56-5b10-4b8c-a07d-648b74557d7c
# Unit 5 # Thermodynamics It is the only physical theory of universal content concerning which I am convinced that, within the framework of the applicability of its basic concepts, it will never be overthrown. — Albert Einstein After studying this Unit, you will be able to: - explain the terms: system and surround...
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Chemistry
105
be41b481-40f8-4c94-bfd7-1855523625da
# THERMODYNAMICS # 5.1 Thermodynamic Terms We are interested in chemical reactions and the energy changes accompanying them. For this we need to know certain thermodynamic terms. These are discussed below. # 5.1.1 The system and the surroundings A system in thermodynamics refers to that part of universe in which ob...
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Chemistry
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d50d3088-6c17-4bb1-8562-6916ad9221ed
# 3. Isolated System In an isolated system, there is no exchange of energy or matter between the system and the surroundings [Fig. 5.2 (c)]. The presence of reactants in a thermos flask or any other closed insulated vessel is an example of an isolated system. # 5.1.3 The state of the system The system must be descri...
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Chemistry
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560d3441-5b72-4c32-83ef-b8beb214849e
# THERMODYNAMICS One way: We do some mechanical work, say 1 kJ, by rotating a set of small paddles and thereby churning water. Let the new state be called B state and its temperature, as TB. It is found that TB > TA and the change in temperature, ∆T = TB–TA. Let the internal energy of the system in state B be UB and t...
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Chemistry
105
87e73f2b-54ce-482d-990a-ee2eac4d40cd
# Chemistry # (c) The general case Let us consider the general case in which a change of state is brought about both by doing work and by transfer of heat. We write change in internal energy for this case as: ∆U = q + w (5.1) For a given change in state, q and w can vary depending on how the change is carried out. ...
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Chemistry
105
73b42ba9-92e4-468b-a421-65aa4027db36
# THERMODYNAMICS inside becomes equal to pex. Let this change be achieved in a single step and the final volume be Vf. During this compression, suppose piston moves a distance, l and is cross-sectional area of the piston is A [Fig. 5.5(a)]. Then, volume change = l × A = ∆V = (Vf – Vi) We also know, pressure = relati...
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Chemistry
105
3a098ba1-f526-4869-92c1-8d2ca683b1e5
142 Processes other than reversible processes are known as irreversible processes. In chemistry, we face problems that can be solved if we relate the work term to the internal pressure of the system. We can relate work to internal pressure of the system under reversible conditions by writing equ...
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Chemistry
105
6b630448-7131-44ed-b132-12e2f1275d6d
# THERMODYNAMICS = 2.303 x 0.8206 x 298 x log 5 = 2.303 x 0.8206 x 298 x 0.6990 = 393.66 L atm # 5.2.2 enthalpy, H # (a) A Useful New State Function We know that the heat absorbed at constant volume is equal to change in the internal energy i.e., ∆U = qV. But most of chemical reactions are carried out not at cons...
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Chemistry
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4b29c178-fce5-4b7e-847f-3a341b2c7292
# Chemistry 1 mol of water is vapourised at 1 bar pressure and 100°C. # Solution (i) The change H₂O (l) → H₂O (g) ∆H = ∆U + ∆ngRT or ∆U = ∆H – ∆ngRT, substituting the values, we get ∆U = 41.00 kJ mol–1 – 1 × 8.3 J mol–1 K–1 × 373 K = 41.00 kJ mol–1 – 3.096 kJ mol–1 = 37.904 kJ mol–1 Fig. 5.6(a) A gas at volume...
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Chemistry
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0bbeb145-48c2-4651-9728-f897a30c7e43
# THERMODYNAMICS of heat required to raise the temperature of one unit mass of a substance by one degree celsius (or one kelvin). For finding out the heat, q, required to raise the temperatures of a sample, we multiply the specific heat of the substance, c, by the mass m, and temperatures change, ∆T as q = c × m × ∆T...
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Chemistry
105
fec79a9f-f218-49b1-b49d-080bf15eb425
# Chemistry # (b) ∆H Measurements Measurement of heat change at constant pressure (generally under atmospheric pressure) can be done in a calorimeter shown in Fig. 5.8. We know that ∆Η = qₚ (at constant p) and, therefore, heat absorbed or evolved, qₚ at constant pressure is also called the heat of reaction or enthalp...
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Chemistry
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4fca14fa-89f1-48a0-8674-7a7fc0a41b5b
# THERMODYNAMICS coefficients of the products and reactants respectively in the balanced chemical equation. For example, for the reaction CH₄ (g) + 2O₂ (g) → CO₂ (g) + 2H₂O (l) ∆ᵣH = ∑a H - ∑b H = [Hₘ (CO₂, g) + 2Hₘ (H₂O, l)] – [Hₘ (CH₄, g) + 2Hₘ (O₂, g)] where Hₘ is the molar enthalpy. Enthalpy change is a very ...
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Chemistry
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