| Sr.No || Test || Specifications
||A white or almost white powder or colourless crystals
||soluble in water, practically insoluble in alcohol.
||A. Solution S is slightly alkaline
B. It complies with the test for loss on drying
C. Solution S gives reaction (b) of phosphates
D. Solution S gives reaction (a) of sodium
||Appearance of solution
||Solution S is clear and colourless
||The solution retains a slight red colour.
||Does not exceed 0.025.
||Not more than 400 ppm.
||Not more than 20 ppm.
||Not more than 0.1 % w/w
||Not more than 4 ppm.
||Not more than 40 ppm.
||Loss on drying
||19.5 per cent to 21.0 per cent
||Not less than 98.0 per cent and not more than the equivalent of 101.0 per cent of Na2HPO4, calculated with reference to the dried substance.