7674. Potassium Sulfate

Nomenclature

CAS number: 7778-80-5
Sulfuric acid potassium salt (1:2); sal polychrestum; arcanum duplicatum; tartarus vitriolatus.
K2O4S; mol wt 174.26.
K 44.87%, O 36.73%, S 18.40%.
K2SO4.

Description and references

Contains at least 99% K2SO4.

Properties

Colorless or white, odorless, hard, bitter crystals, or white granules or powder; permanent in air. d 2.66; mp 1067°. nD20 1.49333-1.49733. One gram dissolves in 8.3 ml water, 4 ml boiling water, 75 ml glycerol. Insol in alcohol. Its soly in water is decreased by KCl or (NH4)2SO4 and is practically insol in a saturated soln of the latter. The aq soln is neutral. pH about 7.

Caution

Swallowing large doses causes severe G.I. irritation.

Use

Technical grades are used in fertilizers for manuf of potassium alum, potassium carbonate and glass; the reagent grade is used in the Kjeldahl determination of nitrogen.

Therapeutic Category

Cathartic.

Keywords

Laxative/Cathartic