Nomenclature
CAS number: 10138-04-2
Sulfuric acid ammonium iron(3+) salt (2:1:1); ferric ammonium sulfate; iron ammonium disulfate.
FeH
4NO
8S
2; mol wt 266.01.
Fe 20.99%, H 1.52%, N 5.27%, O 48.12%, S 24.11%.
NH
4Fe(SO
4)
2.
Description and references
Prepn: Gmelins, Iron (8th ed.) 59, part B, pp 1010-1018 (1932).
Derivative
Dodecahydrate.
Nomenclature
CAS number: 7783-83-7
Ferric alum; iron alum.
FeH
4NO
8S
2.12H
2O; mol wt 482.19.
Fe 11.58%, H 5.85%, N 2.90%, O 66.36%, S 13.30%.
Properties
Colorless to pale-violet, transparent, efflorescent,
octahedral crystals. Odorless; acid styptic taste. mp ≈37°; d 1.71. Very sol in water; practically insol
in alcohol; pH of 0.1M aq soln 2.5.Use
As analytical reagent. Indicator for argentimetric
titrations. Mordant in dyeing and printing textiles.
Therapeutic Category
Astringent, styptic.
Keywords
Astringent