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twg_000012579100 | the precipitate transferred to a tared filter paper, washed, dried and weighed. _Insoluble matter_, remaining on dissolving grammes in water, and filtering. This is washed, dried, ignited and weighed. _Moisture._-- grammes are weighed into a platinum crucible, and heat gently applied. The temperature is gradually incre... | 60 | gutenberg | unknown |
twg_000012579101 | cooled in a desicator, and weighed. _Sulphates_ are estimated by precipitation as barium sulphate and calculated to Na_{}SO_{}. _Sodium._--This may be determined by converting the salt into sodium sulphate by the action of concentrated sulphuric acid, igniting to drive off hydrochloric and sulphuric acids, and fusing t... | 60 | gutenberg | unknown |
twg_000012579102 | be examined, in the same way as sodium chloride, for chloride, insoluble matter, moisture, and sulphate. The potassium may be determined as potassium platino-chloride, as described under carbonate of potash. SILICATES OF SODA AND POTASH. The most important determinations for these are total alkali and silica. _Total al... | 60 | gutenberg | unknown |
twg_000012579103 | with N/ acid, using methyl orange as indicator. _Silica_ may be determined by dissolving gramme in distilled water, rendering the solution acid with HCl, and evaporating to complete dryness on the water-bath, after which the residue is moistened with HCl and again evaporated, this operation being repeated a third time.... | 60 | gutenberg | unknown |
twg_000012579104 | hot dilute HCl, filtered, thoroughly washed, dried, ignited in a tared platinum crucible, and weighed as SiO_{}. ESSENTIAL OILS. As already stated, these are very liable to adulteration, and an examination of all kinds of oil is desirable, while in the case of the more expensive varieties it should never be omitted. _S... | 60 | gutenberg | unknown |
twg_000012579105 | usually taken at C., and compared with water at the same temperature. In the case of otto of rose and guaiac wood oil, however, which are solid at this temperature, it is generally observed at C. compared with water at C. The specific gravity is preferably taken in a bottle or U-tube, but if sufficient of the oil is av... | 60 | gutenberg | unknown |
twg_000012579106 | and a high degree of accuracy is not necessary, it may be taken either with a Westphal balance, or by means of a hydrometer. _Optical Rotation._--For this purpose a special instrument, known as a polarimeter, is required, details of the construction and use of which would be out of place here. Suffice it to mention tha... | 60 | gutenberg | unknown |
twg_000012579107 | part in the determination of the optical activity of certain essential oils, notably in the case of lemon and orange oils. For these Gildemeister and Hoffmann give the following corrections:-- Lemon oil, below C. subtract ' for each degree below, above C. add ' for each degree above. Orange oil, below C. subtract ' for... | 60 | gutenberg | unknown |
twg_000012579108 | add ' for each degree above. _Refractive Index._--This figure is occasionally useful, and is best determined with an Abb refractometer, at C. _Solubility in Alcohol._--This is found by running alcohol of the requisite strength from a burette into a measured volume of the oil with constant agitation, until the oil forms... | 60 | gutenberg | unknown |
twg_000012579109 | quantity of alcohol added, it is well to run in a small further quantity of alcohol, and observe whether any opalescence or cloudiness appears. _Acid_, _ester_, and _saponification values_ are determined exactly as described under fats and oils. Instead of expressing the result as saponification value or number, the pe... | 60 | gutenberg | unknown |
twg_000012579110 | ester present, may be obtained by multiplying the number of c.c. of N/ alkali absorbed in the saponification by the molecular weight of the ester. Thus, to find the percentage as linalyl acetate, the number of c.c. absorbed would be multiplied by . and by , and divided by the weight of oil taken. _Alcohols._--For the e... | 60 | gutenberg | unknown |
twg_000012579111 | the oil contains much ester it must first be saponified with alcoholic potash, to liberate the combined alcohols, and after neutralising the excess of alkali with acid, the oil is washed into a separating funnel with water, separated, dried with anhydrous sodium sulphate, and is then ready for the alcohol determination... | 60 | gutenberg | unknown |
twg_000012579112 | present, this preliminary saponification is unnecessary. The alcohols are estimated by conversion into their acetic esters, which are then saponified with standard alcoholic potash, thereby furnishing a measure of the amount of alcohol esterified. Ten c.c. of the oil is placed in a flask with an equal volume of acetic ... | 60 | gutenberg | unknown |
twg_000012579113 | for an hour to an hour and a half. After cooling, water is added, and the contents of the flask heated on the water-bath for fifteen to thirty minutes, after which they are cooled, transferred to a separating funnel, and washed with a brine solution until the washings cease to give an acid reaction with litmus paper. T... | 60 | gutenberg | unknown |
twg_000012579114 | now dried with anhydrous sodium sulphate, filtered, and - grammes weighed into a flask and saponified with alcoholic potash as in the determination of ester or saponification value. The calculation is a little complicated, but an example may perhaps serve to make it clear. A geranium oil containing . per cent. of ester... | 60 | gutenberg | unknown |
twg_000012579115 | saponification, to liberate the combined geraniol, and . grammes of the acetylated oil required . c.c. of N/ alkali for its saponification. Now every grammes of geranyl acetate present in the acetylated oil correspond to grammes of geraniol, so that for every grammes of ester now present in the oil, grammes have been a... | 60 | gutenberg | unknown |
twg_000012579116 | therefore necessary to make a deduction from the weight of oil taken for the final saponification to allow for this, and since each c.c. of N/ alkali absorbed corresponds to . gramme of geranyl acetate, the amount to be deducted is found by multiplying the number of c.c. absorbed by . gramme, the formula for the estima... | 60 | gutenberg | unknown |
twg_000012579117 | thus becoming in the example given:-- . . Per cent. of geraniol = ---------------------- = . . - (. .) The percentage of combined alcohols can be calculated from the amount of ester found, and by subtracting this from the percentage of total alcohols, that of the free alcohols is obtained. In the example quoted, the es... | 60 | gutenberg | unknown |
twg_000012579118 | per cent. geraniol, and this, deducted from the total alcohols, gives . per cent. free alcohols, calculated as geraniol. This process gives accurate results with geraniol, borneol, and menthol, but with linalol and terpineol the figures obtained are only comparative, a considerable quantity of these alcohols being deco... | 60 | gutenberg | unknown |
twg_000012579119 | isopulegol acetate, so that this is also included in the determination of graniol in citronella oil. _Phenols._--These bodies are soluble in alkalies, and may be estimated by measuring c.c. or c.c. of the oil into a Hirschsohn flask (a flask of about c.c. capacity with a long narrow neck holding c.c., graduated in tent... | 60 | gutenberg | unknown |
twg_000012579120 | a per cent. aqueous caustic potash solution, and warming in the water-bath, then adding another c.c., and after one hour in the water-bath filling the flask with the potash solution until the unabsorbed oil rises into the neck of the flask, the volume of this oil being read off when it has cooled down to the temperatur... | 60 | gutenberg | unknown |
twg_000012579121 | From the volume of oil dissolved the percentage of phenols is readily calculated. _Aldehydes._--In the estimation of these substances, use is made of their property of combining with sodium bisulphite to form compounds soluble in hot water. From - c.c. of the oil is measured into a Hirschsohn flask, about c.c. of a hot... | 60 | gutenberg | unknown |
twg_000012579122 | and the flask immersed in a boiling water bath, and thoroughly shaken at frequent intervals. Further quantities of the bisulphite solution are gradually added, until, after about one hour, the unabsorbed oil rises into the neck of the flask, where, after cooling, its volume is read off, and the percentage of absorbed o... | 60 | gutenberg | unknown |
twg_000012579123 | lemon oil, where the proportion of aldehydes, though of great importance, is relatively very small, it is necessary to first concentrate the aldehydes before determining them. For this purpose, c.c. of the oil is placed in a Ladenburg fractional distillation flask, and c.c. distilled off under a pressure of not more th... | 60 | gutenberg | unknown |
twg_000012579124 | so obtained is separated from the condensed water, measured, dried, and c.c. assayed for aldehydes either by the process already described, or by the following process devised by Burgess (_Analyst_, , ):-- Five c.c. of the oil are placed in the Hirschsohn flask, about c.c. of a saturated solution of neutral sodium sulp... | 60 | gutenberg | unknown |
twg_000012579125 | rosolic acid solution as indicator, and the flask placed in a boiling water-bath and continually agitated. The contents of the flask soon become red owing to the liberation of free alkali by the combination of the aldehyde with part of the sodium sulphite, and this coloration is just discharged by the addition of suffi... | 60 | gutenberg | unknown |
twg_000012579126 | is again placed in the water-bath, the shaking continued, and any further alkali liberated neutralised by more acetic acid, the process being continued in this way until no further red colour is produced. The flask is then filled with the sodium sulphite solution, the volume of the cooled unabsorbed oil read off, and t... | 60 | gutenberg | unknown |
twg_000012579127 | _Solidifying Point, or Congealing Point._--This is of some importance in the examination of anise and fennel oils, and is also useful in the examination of otto of rose. A suitable apparatus may be made by obtaining three test tubes, of different sizes, which will fit one inside the other, and fixing them together in t... | 60 | gutenberg | unknown |
twg_000012579128 | tube is then filled with the oil, and a sensitive thermometer, similar to that described under the Titre test for fats, suspended with its bulb completely immersed in the oil. With anise and fennel, the oil is cooled down with constant stirring until it just starts crystallising, when the stirring is interrupted, and t... | 60 | gutenberg | unknown |
twg_000012579129 | rises noted. This is the solidifying point. In the case of otto of rose, the otto is continually stirred, and the point at which the first crystal is observed is usually regarded as the congealing point. _Melting Point._--This is best determined by melting some of the solid oil, or crystals, and sucking a small quantit... | 60 | gutenberg | unknown |
twg_000012579130 | which is then attached by a rubber band to the bulb of the thermometer, immersed in a suitable bath (water, glycerine, oil, etc.) and the temperature of the bath gradually raised until the substance in the tube is sufficiently melted to rise to the surface, the temperature at which this takes place being the melting po... | 60 | gutenberg | unknown |
twg_000012579131 | otto of rose is usually taken in a similar tube to the setting point, and is considered to be the point at which the last crystal disappears. _Iodine Absorption._--In the authors' opinion, this is of some value in conjunction with other data in judging of the purity of otto of rose. It is determined by Hbl's process as... | 60 | gutenberg | unknown |
twg_000012579132 | Fats and Oils, except that only . to . gramme is taken, and instead of c.c. of chloroform, c.c. of pure alcohol are added. The rest of the process is identical. SOAP. In the analysis of soap, it is a matter of considerable importance that all the determinations should be made on a uniform and average sample of the soap... | 60 | gutenberg | unknown |
twg_000012579133 | otherwise very misleading and unreliable figures are obtained. Soap very rapidly loses its moisture on the surface, while the interior of the bar or cake may be comparatively moist, and the best way is to carefully remove the outer edges and take the portions for analysis from the centre. In the case of a household or ... | 60 | gutenberg | unknown |
twg_000012579134 | is imperative that the quantities for analysis should all be weighed out as quickly after each other as possible. _Fatty Acids._--Five grammes of the soap are rapidly weighed into a small beaker, distilled water added, and the beaker heated on the water bath until the soap is dissolved. A slight excess of mineral acid ... | 60 | gutenberg | unknown |
twg_000012579135 | heated until the separated fatty acids are perfectly clear, when they are collected on a tared filter paper, well washed with hot water and dried until constant in weight. The result multiplied by gives the percentage of fatty acids in the sample. A quicker method, and one which gives accurate results when care is best... | 60 | gutenberg | unknown |
twg_000012579136 | in the manner described above as far as the decomposition with mineral acid, and to then add or grammes of stearic acid or beeswax to the contents of the beaker and heat until a clear layer of fatty matter collects upon the acid liquor. Cool the beaker, and when the cake is sufficiently hard, remove it carefully by mea... | 60 | gutenberg | unknown |
twg_000012579137 | a spatula and dry on a filtering paper, add the portions adhering to the sides of the beaker to the cake, and weigh. The weight, less the amount of stearic acid or beeswax added, multiplied by gives the percentage of fatty acids. Care must be taken that the cake does not contain enclosed water. The results of these met... | 60 | gutenberg | unknown |
twg_000012579138 | returned as fatty acids, but are in reality insoluble fatty acids, the soluble fatty acids being generally disregarded. However in soaps made from cocoa-nut and palm-kernel oils (which contain an appreciable quantity of soluble fatty acids) the acid liquor is shaken with ether, and, after evaporation of the ethereal ex... | 60 | gutenberg | unknown |
twg_000012579139 | result already obtained as above, or the ether method described below may be advantageously employed. Where the soap under examination contains mineral matter, the separated fatty acids may be dissolved in ether. This is best performed in an elongated, graduated, stoppered tube, the total volume of the ether, after sub... | 60 | gutenberg | unknown |
twg_000012579140 | dryness in a tared flask, which is placed in the oven at C. until the weight is constant. In a complete analysis, the figure for fatty acids should be converted into terms of fatty anhydrides by multiplying by the factor .. In this test the resin acids contained in the soap are returned as fatty acids, but the former c... | 60 | gutenberg | unknown |
twg_000012579141 | be estimated, as described later, and deducted from the total. _Total Alkali._--The best method is to incinerate grammes of the soap in a platinum dish, dissolve the residue in water, boil and filter, making the volume of filtrate up to c.c., the solution being reserved for the subsequent determination of salt, silicat... | 60 | gutenberg | unknown |
twg_000012579142 | the solution are titrated with N/ acid, to methyl orange, and the result expressed in terms of Na_{}O. Number of c.c. required . = per cent. Na_{}O. The total alkali may also be estimated in the filtrate from the determination of fatty acids, if the acid used for decomposing the soap solution has been measured and its ... | 60 | gutenberg | unknown |
twg_000012579143 | titrating back the excess of acid with normal soda solution, when the difference will equal the amount of total alkali in the quantity taken. The total alkali is usually expressed in the case of hard soaps as Na_{}O, and in soft soaps as K_{}O. _Free caustic alkali_ is estimated by dissolving grammes of the soap, in ne... | 60 | gutenberg | unknown |
twg_000012579144 | gentle heat, filtering, well washing the filter with hot neutral spirit, and titrating the filtrate with N/ acid, to phenol-phthalein. Number of c.c. required . = per cent. free alkali Na_{}O, as caustic. _Free Carbonated Alkali._--The residue on the filter paper from the above determination is washed with hot water, a... | 60 | gutenberg | unknown |
twg_000012579145 | orange as indicator. The result is generally expressed in terms of Na_{}O. Number of c.c. required . = per cent. free alkali Na_{}O, as carbonate. _Free Alkali._--Some analysts determine the alkalinity to phenol-phthalein of the alcoholic soap solution without filtering, and express it as free alkali (caustic, carbonat... | 60 | gutenberg | unknown |
twg_000012579146 | alkali and free alkali (caustic and carbonate together) represents the alkali combined with fatty acids. This figure may also be directly determined by titrating, with N/ acid, the alcoholic solution of soap after the free caustic estimation, using lacmoid as indicator. The potash and soda in soaps may be separated by ... | 60 | gutenberg | unknown |
twg_000012579147 | _Pearl ash_ (page ). The potassium platino-chloride (K_{}PtCl_{}) is calculated to potassium chloride (KCl) by using the factor ., and this figure deducted from the amount of mixed chlorides found, gives the amount of sodium chloride (NaCl), from which the sodium oxide (Na_{}O) is obtained by multiplying by .. The pota... | 60 | gutenberg | unknown |
twg_000012579148 | (K_{}O) by the use of the factor .. _Salt_ may be determined in c.c. of the filtered aqueous extract of the incinerated soap, by exactly neutralising with normal acid and titrating with N/ silver nitrate solution, using a neutral solution of potassium chromate as indicator. The final reaction is more distinctly observe... | 60 | gutenberg | unknown |
twg_000012579149 | to the solution. Number of c.c. required . = per cent. of common salt, NaCl. Chlorides may also be estimated by Volhard's method, the aqueous extract being rendered slightly acid with nitric acid, a measured volume of N/ silver nitrate solution added, and the excess titrated back with N/ ammonium thiocyanate solution, ... | 60 | gutenberg | unknown |
twg_000012579150 | by evaporating c.c. of the filtered extract from the incinerated soap, in a platinum dish with hydrochloric acid twice to complete dryness, heating to C., adding hot water, and filtering through a tared filter paper. The residue is well washed, ignited, and weighed as SiO_{}, and from this silica is calculated the sodi... | 60 | gutenberg | unknown |
twg_000012579151 | filtrate from the silica estimation by precipitation with barium chloride solution, and weighing the barium sulphate, after filtering, and burning, expressing the result in terms of Na_{}SO_{} by the use of the factor .. _Moisture._--This is simply estimated by taking a weighed portion in small shavings in a tared dish... | 60 | gutenberg | unknown |
twg_000012579152 | to lose weight. From the loss thus found is calculated the moisture percentage. _Free or Uncombined Fat._--This is usually determined by repeated extraction of an aqueous solution of the soap with petroleum ether; the ethereal solution, after washing with water to remove traces of soap, is evaporated to dryness and the... | 60 | gutenberg | unknown |
twg_000012579153 | for employment where many determinations have to be performed, is to dissolve grammes of soap in c.c. neutral alcohol and titrate to phenol-phthalein with N/ acid. Add - drops HCl and boil to expel carbonic acid, neutralise with alcoholic KOH solution and add exactly c.c. in excess, boil for fifteen minutes under a ref... | 60 | gutenberg | unknown |
twg_000012579154 | The difference between this latter figure and the amount required for a blank test with c.c. alcoholic KOH, denotes the amount of alkali absorbed by the uncombined fat. _Examination of the fatty acids_ as a guide to the probable composition of the soap:-- From the data obtained by estimating the "titre," iodine number,... | 60 | gutenberg | unknown |
twg_000012579155 | and rosin acids, and the rosin content, a fairly good idea of the constitution of the soap may be deduced. The titre, iodine number, and saponification equivalent are determined in exactly the same manner as described under Fats and Oils. The presence of rosin may be detected by the Liebermann-Storch reaction, which co... | 60 | gutenberg | unknown |
twg_000012579156 | fatty acids in acetic anhydride, and adding to a few drops of this solution drop of per cent. sulphuric acid. A violet coloration is produced with rosin acids. The amount of rosin may be estimated by the method devised by Twitchell (_Journ. Soc. Chem. Ind._, , ) which is carried out thus:-- Two grammes of the mixed fat... | 60 | gutenberg | unknown |
twg_000012579157 | acids are dissolved in c.c. absolute alcohol, and dry hydrochloric acid gas passed through until no more is absorbed, the flask being kept cool by means of cold water to prevent the rosin acids being acted upon. The flask, after disconnecting, is allowed to stand one hour to ensure complete combination, when its conten... | 60 | gutenberg | unknown |
twg_000012579158 | well washed out with water so that the volume is increased about five times, and boiled until the acid solution is clear, a fragment of granulated zinc being added to prevent bumping. The heat is removed, and the liquid allowed to cool, when it is poured into a separator, and the beaker thoroughly rinsed out with ether... | 60 | gutenberg | unknown |
twg_000012579159 | acid liquor is withdrawn, and the ethereal layer washed with water until free from acid. Fifty c.c. neutral alcohol are added, and the solution titrated with N/ KOH or NaOH solution, the percentage of rosin being calculated from its combining weight. Twitchell suggests as the combining weight of rosin, but is a closer ... | 60 | gutenberg | unknown |
twg_000012579160 | out gravimetrically, in which case petroleum ether, boiling at C. is used for washing out the beaker into the separator. The acid liquor is run off, and the petroleum ether layer washed first with water and then with a solution of / gramme KOH and c.c. alcohol in c.c. water, and agitated. The rosin is thus saponified a... | 60 | gutenberg | unknown |
twg_000012579161 | resinate solution is withdrawn, acidified, and the resin acids collected, dried and weighed. _Halphen's Reaction._--This is a special test to determine the presence or absence of cotton-seed oil fatty acids in mixtures. Equal parts of the fatty acids, amyl alcohol, and a per cent. solution of sulphur in carbon bisulphi... | 60 | gutenberg | unknown |
twg_000012579162 | effervescence ceases, then in boiling brine for one hour or longer when only small quantities are present. The presence of cotton-seed oil is denoted by a pink coloration. The reaction is rendered much more rapid, according to Rupp (_Z. Untersuch. Nahr. Genussm._, , , ), by heating in a stoppered flask. Other bodies wh... | 60 | gutenberg | unknown |
twg_000012579163 | for or determine in soap include:-- _Carbolic acid._--Fifty grammes of the soap are dissolved in water and c.c. of per cent. caustic potash added. The solution is treated with an excess of brine, the supernatant liquor separated, and the precipitate washed with brine, the washings being added to the liquor withdrawn. T... | 60 | gutenberg | unknown |
twg_000012579164 | in a Muter's graduated tube, and acidified with mineral acid. The volume of separated phenols is observed and stated in percentage on the soap taken. Or the alkaline layer may be rendered acid and steam distilled; the distillate is made up to a known volume, and a portion titrated by the Koppeschaar method with standar... | 60 | gutenberg | unknown |
twg_000012579165 | soap are dissolved in water, decomposed with dilute sulphuric acid, and the clear fatty acids filtered and washed. The filtrate is neutralised with barium carbonate, evaporated to c.c., and the glycerol estimated by the bichromate method detailed under Crude Glycerine. _Starch_ or _gum_ may be detected by dissolving th... | 60 | gutenberg | unknown |
twg_000012579166 | paper. Starch is readily recognised by the blue coloration it gives with a solution of iodine in potassium iodide. _Sugars_ are tested for by means of Fehlings' solution, in the liquor separated from the fatty acids, after first boiling with dilute acid to invert any cane sugar. _Mercury_ will be revealed by a black pr... | 60 | gutenberg | unknown |
twg_000012579167 | added to the liquor separated from the fatty acids, and may be estimated by filtering off this precipitate on a tared Gooch's crucible, which is then dried and weighed. _Borax or borates_ are tested for in the residue insoluble in alcohol. This is dissolved in water, rendered faintly acid with dilute hydrochloric acid,... | 60 | gutenberg | unknown |
twg_000012579168 | for a few minutes in the liquid. This is then dried in the water-oven, when if any boric acid compound is present, a bright reddish-pink stain is produced on the paper, which is turned blue on moistening with dilute alkali. The amount of the boric acid radicle may be determined by incinerating - grammes of soap, extrac... | 60 | gutenberg | unknown |
twg_000012579169 | acid, filtering, neutralising this solution to methyl orange, and boiling to expel carbon dioxide. After cooling, sufficient pure neutralised glycerine is added to form one-third of the total volume, and the liquid titrated with N/ caustic soda solution, using phenol-phthalein as indicator. Each c.c. of N/ NaOH solutio... | 60 | gutenberg | unknown |
twg_000012579170 | borax, Na_{}B_{}O_{}10H_{}O. LYES. The amounts of caustic alkali (if any), carbonated alkali, and salt present are determined in the manner already described under Alkali and Alkali Salts. The glycerol content is ascertained by taking . grammes, adding lead subacetate solution, and filtering without increasing the bulk... | 60 | gutenberg | unknown |
twg_000012579171 | oxidation with bichromate and sulphuric acid conducted as described in the examination of Crude Glycerine. The solution, after oxidation, is made up to c.c., and titrated against standard ferrous ammonium sulphate solution, the formula for the calculation being:-- {. - .} Per cent. of glycerol = { ---} { n } where n eq... | 60 | gutenberg | unknown |
twg_000012579172 | lyes required to oxidise the ferrous ammonium sulphate solution. The estimation of actual glycerol in this is necessarily a matter of considerable importance, and a very large number of processes, which are constantly being added to, have been suggested for the purpose. Hitherto, however, only two methods have been gen... | 60 | gutenberg | unknown |
twg_000012579173 | results obtained by these do not invariably agree, the latter, which includes all oxidisable matter as glycerol, giving sometimes considerably higher results, and it has been suggested that a determination should be made by both methods, and the average of the two results considered the true value. This involves a cons... | 60 | gutenberg | unknown |
twg_000012579174 | be found sufficient in a works laboratory to determine the glycerol by one method only in the ordinary course, reserving the other process for use as a check in case of dispute or doubt. _Acetin Method._--This consists in converting the glycerol into its ester with acetic acid, the acetic triglyceride, or triacetin bei... | 60 | gutenberg | unknown |
twg_000012579175 | known volume of standard alkali, the excess of which is titrated with acid, and the percentage of glycerol calculated from the amount of alkali absorbed. From to . grammes of the glycerine is weighed into a conical flask of about c.c. capacity, or c.c. of acetic anhydride added, together with about grammes of anhydrous... | 60 | gutenberg | unknown |
twg_000012579176 | on a sand-bath under a reflux condenser for one to one and a half hours, after which it is allowed to cool, c.c. water added, and the ester dissolved by shaking, and gently warming, the reflux condenser still being attached as the acetin is very volatile. The solution is then filtered from a white flocculent precipitat... | 60 | gutenberg | unknown |
twg_000012579177 | the impurities, into a larger conical flask, of some - c.c. capacity, and after cooling, rendered just neutral to phenol-phthalein by means of N/ caustic soda solution, the exact point being reached when the solution acquires a reddish-yellow tint; c.c. of a strong caustic soda solution is then added, and the liquid bo... | 60 | gutenberg | unknown |
twg_000012579178 | alkali being titrated after cooling, with N/ or N/ hydrochloric acid. A blank experiment is carried out simultaneously, with another c.c. of the soda solution, and the difference in the amounts of acid required by the two, furnishes a measure of the alkali required to saponify the acetin formed, and hence the amount of... | 60 | gutenberg | unknown |
twg_000012579179 | be calculated. _Example._--. grammes crude glycerine, after treatment with acetic anhydride, and neutralising, was saponified with c.c. of a per cent. caustic soda solution. The blank experiment required . c.c. N/ hydrochloric acid. Flask containing acetin " . c.c. " " ----- . c.c. " " Hence, the acetin formed from the... | 60 | gutenberg | unknown |
twg_000012579180 | glycerine required . c.c. N/ caustic alkali for its saponification, so that the percentage of glycerol may be calculated from the following formula:-- . . Per cent. glycerol = --------------------- = .. . _Bichromate Method._--This process was originally devised by Hehner (_Journ. Soc. Chem. Ind._, , -), but the modifi... | 60 | gutenberg | unknown |
twg_000012579181 | by the authors, and has been practised by them for several years with perfectly satisfactory results. Twenty-five grammes of the crude glycerine are weighed out in a beaker, washed into a c.c. stoppered flask, and made up to the graduation mark with water. Twenty-five c.c. of this solution are then measured from a bure... | 60 | gutenberg | unknown |
twg_000012579182 | excess of basic lead acetate solution added to precipitate organic matter, the precipitate allowed to settle, and the supernatant liquid poured through a filter paper into another c.c. flask. The precipitate is washed by decantation until the flask is nearly full, then transferred to the filter, and allowed to drain, a... | 60 | gutenberg | unknown |
twg_000012579183 | precipitate the slight excess of basic lead acetate solution, and the contents of the flask made up with water to c.c. This solution is filtered, c.c. measured from a burette into a conical flask of about c.c. capacity, c.c. of a standard potassium bichromate solution containing . grammes bichromate per litre added, to... | 60 | gutenberg | unknown |
twg_000012579184 | and the whole placed in a boiling water-bath for one hour, after which it is allowed to cool, diluted with water to c.c., and this solution run in to c.c. of a per cent. ferrous ammonium sulphate solution until the latter is completely oxidised, as shown by no blue coloration being produced when one drop is brought int... | 60 | gutenberg | unknown |
twg_000012579185 | one drop of a freshly prepared solution of potassium ferricyanide on a spot-plate. The ferrous ammonium sulphate solution is previously standardised by titration with a potassium bichromate solution of one-tenth the above strength, made by diluting c.c. of the strong solution to c.c. with water. The reaction taking pla... | 60 | gutenberg | unknown |
twg_000012579186 | 7K_{}Cr_{}O_{} + 28H_{}SO_{} = 9CO_{} + 40H_{}O + 7K_{}SO_{} + 7Cr_{}(SO_{})_{}. Now the strong potassium bichromate solution above mentioned is of such a strength that c.c. will oxidise . gramme glycerine, and c.c. of the ferrous ammonium sulphate solution should require about c.c. of the one-tenth strength bichromate... | 60 | gutenberg | unknown |
twg_000012579187 | then the amount of ferrous ammonium sulphate solution which would require exactly c.c. (corresponding to . gramme glycerine) is calculated, and the oxidised glycerine solution run into this until oxidation is complete. The formula for the calculation of the percentage of glycerol then becomes:-- {. -( .)} Per cent. of ... | 60 | gutenberg | unknown |
twg_000012579188 | n equals the number of c.c. of oxidised glycerine solution required to oxidise the ferrous ammonium sulphate solution. Example:-- In the blank experiment c.c. ferrous ammonium sulphate solution required . c.c. one-tenth strength bichromate solution, so that . c.c. ferrous solution would equal c.c. bichromate. . c.c. fe... | 60 | gutenberg | unknown |
twg_000012579189 | give a blue coloration with potassium ferricyanide. {. - ( .)} Therefore, per cent. of glycerol = { ------------} { . } = . per cent. Other methods have been suggested for the preliminary purification, _e.g._, silver oxide, silver carbonate and lead subacetate, and copper sulphate and caustic potash, but the lead subac... | 60 | gutenberg | unknown |
twg_000012579190 | determinations include those of specific gravity, alkalinity, proportion of salts and chloride, and tests for metals, arsenic, sulphur compounds, sugar, and fatty acids. _Specific gravity_ is determined at C., and may be taken in specific gravity bottle, or with a Westphal balance or hydrometer It usually ranges from .... | 60 | gutenberg | unknown |
twg_000012579191 | somewhat considerable if the soap has been grained with caustic alkali, is determined after dilution with water by titrating with N/ acid, using methyl orange as indicator. _Salts._--These may be determined by gently incinerating - grammes of the glycerine, extracting the carbonaceous mass with distilled water, filteri... | 60 | gutenberg | unknown |
twg_000012579192 | salts in the weight taken. _Chloride of sodium_ (common salt) may be estimated by dissolving the total salts in water, adding potassium chromate, and titrating with N/ silver nitrate solution. _Copper_, _lead_, _iron_, _magnesium_, and _calcium_ may also be tested for in the salts, by ordinary reactions. _Arsenic_ is b... | 60 | gutenberg | unknown |
twg_000012579193 | in a test-tube, a few fragments of granulated zinc free from arsenic, and c.c. dilute hydrochloric acid added, and the mouth of the tube covered with a small filter paper, moistened three successive times with an alcoholic solution of mercury bichloride and dried. After thirty minutes the filter paper is examined, when... | 60 | gutenberg | unknown |
twg_000012579194 | is present. _Sulphates._--These may be precipitated with barium chloride in acid solution, in the usual way, dried, ignited, and weighed. _Sulphites_ give with barium chloride a precipitate soluble in hydrochloric acid. If the precipitate is well washed with hot water, and a few drops of iodine solution together with s... | 60 | gutenberg | unknown |
twg_000012579195 | gradual disappearance of the blue starch-iodine compound first formed. _Thiosulphates_ are detected by precipitating any sulphite and sulphate with barium chloride, filtering, acidifying, and adding a few drops of potassium permanganate solution, when in the presence of a mere trace of thiosulphate, the solution become... | 60 | gutenberg | unknown |
twg_000012579196 | in the Gutzeit arsenic test. Any sulphide causes a blackening of the lead acetate paper. _Sugars_ may be tested for both before and after inversion, by boiling with Fehlings' solution, when no reduction should take place, if pure. _Fatty acids_ are detected by the turbidity they produce when the diluted glycerine is ac... | 60 | gutenberg | unknown |
twg_000012579197 | the year the amount of soap produced annually in this country was readily obtainable from the official returns collected for the purpose of levying the duty, and the following figures, taken at intervals of ten years for the half century prior to that date, show the steady development of the industry during that period... | 60 | gutenberg | unknown |
twg_000012579198 | | | Year. | Manufactured. | Consumed. | Exported. | Duty per Ton. | |_______|_______________|___________|___________|_______________| | | | | | | | | Cwts. | Cwts. | Cwts. | | | | , | , | , | | | | , | , | , | | | | , | , | , | | | | ,, | 60 | gutenberg | unknown |
twg_000012579199 | | , | , | | | | ,, | ,, | , | | | | ,, | ,, | , | | |_______|_______________|___________|___________|_______________| Since the repeal of the soap duty, the revenue from which had reached about ,, per annum, no accurate means of gauging the production exists, but it is estimated that it has nearly quadrupled during | 60 | gutenberg | unknown |
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