Phosphoric acid for industrial use (including foodstuffs) — Determination of chloride content — Pote...
Applicable to products having Cl- contents, expressed as chlorine, equal to or more than 0.001 % (m/m). The lower limit can be extended downwards by using weaker standard reference and volumetric solutions. Describes potentiometric titration of the ions with silver nitrate solution in a nitric acid-acetone-water medium using a silver measurement electrode and a calomel reference electrode.
Phosphoric acid for industrial use (including foodstuffs) — Determination of oxides of nitrogen cont...
Applicable to products having a content, expressed as N, equal to or more than 0.2 mg/kg. Consists in oxidation of nitrous nitrogen to nitric nitrogen by potassium permanganate and reaction of nitrogen(V) with 3,4-xylenol under specified conditions to form a nitrate derivative. Subsequent destillation of the nitrate derivative and absorption in sodium hydroxide solution. Spectrophotometric…
Phosphoric acid for industrial use (including foodstuffs) — Determination of total phosphorus (V) ox...
Applicable to products whether or not they are homogeneous and whether or not they contain polyphosphoric acids. Specifies preliminary hydrolysis of the polyphosphoric acids by boiling in the presence of hydrochloric acid. The precipitation of the phosphoric acid is carried out in the form of quinoline phosphomolybdate in the presence of acetone. Filtration by a filter crucible, washing, drying…
Sodium hydroxide for industrial use — Determination of calcium and magnesium contents — Flame atomic...
Applicable to products having contents of more than 2.5 mg Ca/kg and 0.5 mg Mg/kg if an acetylene-air flame is used or 0.6 mg Ca/kg and 1.0 mg Mg/kg if an acetylen-dinitrogen monoxide flame is used. The principle consists in the acidification of a test portion with hydrochloric acid, aspiration of the solution into an acetylene-dinitrogen monoxide flame or acetylene-air flame. In the latter case…
The method is applicable to the determination of nickel contents up to 2.5 % (m/m). Covers principle, reagents, apparatus, sampling, procedure, expression of results, and test report.
Steel, non-alloy and low-alloy — Determination of depth of decarburization
Defines carburization and specifies three methods of measuring the depth of decarburization of non-alloy and low-alloy steels (micrographic method, method of measuring the micro-hardness and methods of determination of carbon content).
Washing powders — Determination of total phosphorus(V) oxide content — Quinoline phosphomolybdate gr...
The determination is carried out in the following way: Hydrolysis of polyphosphates by nitric acid. Precipitation of phosphates in the form of quinoline phosphomolybdate in acetone solution. Drying and weighing of the precipitate.
Copper alloys — Determination of iron content — 1,10- Phenanthroline spectrophotometric method
The method is applicable to the determination of iron contents up to 0.4 % (m/m) in any of the copper alloys listed in ISO publications. ISO 1812 specifies principle, reagents, apparatus, sampling, procedure, expression of results and test report.
Milk — Determination of fat content (Routine method)
Is applicable to liquid milk, whole or partially skimmed, raw or pasteurized. The method specified is based on the saparation of the fat of the milk in a butyrometer by centrifuging after the protein has been dissolved with sulphuric acid. The procedure for checking the capacity of the milk pipette is described in an annex.
