562. Ammonium Thiosulfate

Nomenclature

CAS number: 7783-18-8
Thiosulfuric acid (H2S2O3) ammonium salt (1:2); Ammonium hyposulfite.
H8N2O3S2; mol wt 148.21.
H 5.44%, N 18.90%, O 32.39%, S 43.27%.
(NH4)2S2O3.

Description and references

Prepn: Gmelins, Ammonium (8th ed.) 23, pp 304-306 (1936). Crystal structure: S. T. Teng et al., Acta Crystallogr. B35, 1682 (1979).

Properties

Crystals, dec at 150°. Sol in water; insol in alc, ether.

Use

To clean “white” metal; in photography; in lubricants for metal cold-working.