| 释义 |
iron alum
a. Min. A double sulphate of iron and aluminium (see alum n. 2), occurring native as halotrichite.
b. Chem. A double sulphate of iron and potassium (or ammonium), belonging to the series of alums in the extended sense: see alum n. 3).
1868Dana Min. 654 Halotrichite..Iron Alum. 1868–72Watts Dict. Chem. V. 596 Ammonio-ferric sulphate, or Ammonia-iron-alum..Potassio-ferric sulphate, or Potash⁓iron-alum. 1876Harley Mat. Med. 192 Iron alum results when the alumina is replaced by peroxyde of iron. |