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Gives general intructions and specifies the methods for the determination of density at 20 °C, for the determination of boiling range, for the determination of dry residue after evaporation on a water bath, for the measurement of colour, for the determination of water content and of aldehydes and ketones content. International Standards ISO 756/1, ISO 756/2 and ISO 756/3 cancel and replace ISO…

The method is applicable to products having esters contents in the range 0.005 % (m/m) to 0.15 % (m/m). The principle consists in the saponification of esters present in a test portion by boiling with excess standard volumetric sodium hydroxide solution; determination of the residual sodium hydroxide, and hence the amount used for saponification, by titration with standard volumetric hydrochloric…

The method is applicable to products having carbonyl compounds contents between 0.00025 % (m/m) and 0.01 % (m/m). The principle is based on reaction in acid medium of the carbonyl compounds in a test portion with 2,4-dinitrophenylhydrazine. Formation of the corresponding 2,4-dinitrophenylhydrazones which, after making the solution alkaline, take on a red coloration. Photometric measurement of…

The method is applicable to products having carbonyl compounds contents equal to or greater than 0.01 % (m/m). The method only allows determination of those carbonyl compounds which react under the specified conditions. The principle is based on the reaction of hydroxylammonium chloride with the carbonyl compounds in a test portion and titration of the hydrochloric acid formed with standard…

The method is applicable to products having aldehyde contents in the range 0.00025 % (m/m) to 0.00125 % (m/m). The principle is based on the reaction of the aldehydes present in a test portion with Schiff reagent. Visual comparison of the colour obtained with the colours of standard colorimetric solutions containing known quantities of acetaldehyde. - International Standards ISO 1388/1 to ISO…

The principle is based on the conversion of methanol present in a test portion to formaldehyde by oxidation. The oxidation is carried out with a solution of potassium permanganate in phosphoric acid. Reaction of the formaldehyde formed with chromotropic acid (4,5-dihydroxynaphthalene-2,7-disulphonic acid). Photometric measurement of the violet coloration obtained at a wavelength of about 570 nm…

The principle is based on the conversion of the methanol present in a test portion to formaldehyde by oxidation with a solution of potassium permanganate in phosphoric acid. Reaction of the formaldehyde formed with Schiff reagent. Visual comparison of the colour obtained with the colours of standard colorimetric solutions containing known quantities of formaldehyde. - International Standards ISO…

The principle is based on distillation of a test portion in the presence of water, addition to the distillate of a saturated sodium chloride solution and measurement of the volume of insoluble hydrocarbons. A Hempel fractionating column with Liebig condenser is used for the distillation. - International Standards ISO 1388/1 to ISO 1377/12 cancel and replace ISO Recommendation R 1388-1970 of which…

The document also specifies the methods to be used for the determination of density at 20 °C, for the determination of dry residue after evaporation on a water bath, for the determination of water content, and for the measurement of colour. - International Standards ISO 1388/1 to 1388/12 cancel and replace ISO Recommendation R 1388-1970 of which they constitute a technical revision.

The principle of the determination consists in reaction of the acetaldehyde present in a test portion with an excess of sodium hydrogen sulphite solution, and iodometric titration of the residual sodium hydrogen sulphite. The method is applicable to products having acetaldehyde monomer contents equal to or greater than 0,01 % (m/m). This International Standard as also been approved by the…