action and use
sodium dihydrogen phosphate monohydrate contains not less than 98. 0 and not more than 100. 5% of nah2po4, calculated with reference to the dried substance.
colourless crystals or a white powder.
very soluble in water; very slightly soluble inethanol (96%).
dissolve 10. 0 g in sufficient carbon dioxide-free water prepared from distilled water to produce 100 ml (solution s).
a. Solution s is faintly acid.
b. Solution s yields the reactions characteristic of phosphates.
c. Solution s neutralized with a 10% w/v solution of potassium hydroxide yields reaction a characteristic of sodium salts.
d. Complies with the test for loss on drying.
ph of a mixture of 5 ml of solution s and 5 ml of carbon dioxide-free water , 4. 2 to 4. 5.
clarity and colour of solution
solution s is clear and colourless.
0. 5 g complies with the limit test for arsenic - 2 ppm.