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For the analysis of milk and dairy products use background electrolyte G – solution of chloride ammonium With (NH4Cl) = 1 mol/dm ³ and ammonia C (NH = 1 mol/dm ³; 53,49 g of chloride ammonium dissolve in a small amount of water, transfer to a measured flask with a capacity of 1000 cm ³. Add water solution of ammonia in such volume which contains 17 g of ammonia to a flask. The necessary volume of solution of ammonia is counted on the basis of density indicators measured by the areometer (about 75 cm ³). Volume in a flask is brought water to a tag.

Lead nitrate is recrystallized and dry up at (104 + °C up to the constant weight. 1,599 g of the dried-up salt dissolve in the small volume of bidistillirovanny water and quantitatively transfer to a measured flask with a capacity of 1000 cm ³. Add 5 cm to a flask ³ nitric acid with a density of 1,40 g/cm ³ and bring solution volume to a tag bidistillirovanny water.

The laboratory glasswares is washed out chromic mix, water. Nitric acid with a density of 1,40 g/cm ³, several times distilled and twice bidistillirovanny water also dry up. Then wash out solution of a ditizon 0,01 g/dm ³. Even at minor change of coloring carry out several times processing the ditizony: fill ware with solution of a ditizon of 0,30 g/dm ³ and maintain every time for 30 min. then wash out chloroform and repeat processing, using solution of a ditizon of 0,01 g/dm ³. Wash out chloroform and dry up on air in an exhaust case.

The laboratory glasswares is washed out chromic mix,, nitric acid with a density of 1,40 g/cm3, several times and twice bidistillirovanny bathing water and dried up. Then solution of a ditizon 0,01 g/dm ³. Even at minor change of coloring carry out several times processing the ditizony: fill ware with solution of a ditizon of 0,30 g/dm3 and maintain every time for 30 min. then wash out chloroform and repeat processing, using solution of a ditizon of 0,01 g/dm

Bring an additive in the second flask - standard solution in such quantity that lead peak height on a polyarogramma approximately doubled in comparison with the initial. The additive should be brought in small volume (no more than 1 cm to prevent change of concentration of background electrolyte and cindery elements. Then add background electrolyte or a bidistillirovanny to a flask (during the work with background electrolyte in the volume necessary for finishing it to 5 cm Pass inert gas, in the same conditions and measure lead peak height.

Values of a mean square deviation of a casual component of an error of measurements of a mass fraction of lead of the same test in different laboratories at the changes of the influencing factors allowed by a technique makes 0,22 * X.

Take an arithmetic average of results (X) two parallel definitions for final result, the allowed between which should not exceed at P = 0,95 30% on an to an arithmetic average. The final result is to the second decimal sign.

The method is based on a dry mineralization (combustion) of test with use as a supportive application of nitric acid and quantitative definition of copper a polyarografirovaniye in the mode of alternating current.

The method is based on a dry mineralization (combustion) of test with use as a supportive application of nitric acid and quantitative definition of lead a polyarografirovaniye in the mode of alternating current.

The method is based on a dry mineralization (combustion) of test with use as a supportive application of nitric acid and quantitative definition of cadmium a polyarografirovaniye in the mode of alternating current.

In the analysis of dairy products use background electrolyte A – the mixed solution of ortofosforny acid C (H3PO = 1,3 mol/dm ³ and chloric acid C (HSLO = 0,7 mol/dm ³: mix the diluted ortofosforny, chloric acid and bidistillirovanny water in the ratio 3:2:

Standard solutions of necessary concentration are prepared consecutive dilution in 10, 100 and 1000 times of the main solution of lead. At measurement of concentration of lead in the examinee solution with use of background electrolyte A dilution is carried out bidistillirovanny water.