AMMONIUM THIOSULPHATE – PHOTOGRAPHIC GRADE

A. SPECIFICATIONS

 


1.

Ammonium thiosulphate (as (NH4)2S2O3), percent by weight. (Min)

97.0%

2.

Sulphite
 (as (NH4)2SO3), percent by weight.  ((Max)

2

3.

Acidity

To pass test

4.

Alkalinity (as (NH4OH), percent by weight. (Max)

0.2

5.

Moisture

To pass test

6.

Sulphide (as (NH4)2S), percent by weight,  (Max)

0.002

7.

Insoluble matter, calcium, magnesium, ammonium hydroxide precipitate, percent by weight,  (Max)

0.4

8.

Residue after ignition, percent by weight, (Max)

0.2

9.

Iron (as Fe), percent by weight, (Max)

0.005

10.

Heavy metals (as pb). Percent by weight, (Max)

0.002

11.

Appearance of solution

To pass test

B. QUANTITY OF SAMPLE REQUIRED FOR TEST : 250 gms

C. MODE OF PACKING

           The material shall be packed in polyethylene bag and repacked in air – tight containers or in such other containers agreed to between the purchaser and the supplier.