FE

Take 1.0g sodium metabisulfite, add 5ml water and dissolve with 2ml hydrochloric acid, evaporated to dryness on the water bath. Add 15 ml water and 2 ml hydrochloric acid to the residue, after dissolving, add proper Bromine solution to make the solution yellowish, heat and remove excess bromine, cool it, add water into 25ml. Comparing with the contrast solution of 2.0 ml standard Fe solution, must not deeper. Check.

HEAVY METAL

Take 1.0g sodium metabisulfite, add 10ml water, after dissolving add 5ml hydrochloric acid, evaporated to dryness on the water bath, add 15ml water into the residue, boil slowly for 2 minutes, filter, add proper Bromine solution to make clarify, heat and remove excess bromine, cool it, add 1 drop of phenolphthalein solution and proper Ammonia solution to make the solution pink, add 2ml acetate buffer (Ph 3.5) and proper water into 25ml. Check.

ARSENIC

Take 1.0g sodium metabisulfite, add 4ml water, after dissolving add 3ml nitric acid, evaporated to dryness on the water bath, add a few ml water into the residue, Stir well, filter, rinse the filter residue with water, combine lotion and filtrate, evaporated to dryness, add 5ml hydrochloric acid and 23ml water, check after dissolving.

PH

Take 5.0g sodium metabisulfite, add 50 ml distilled water and dissolve, test it by PH meter.

How To Test The Composition Content Of Sodium Metabisulfite