double salt

American  

noun

Chemistry.

1. a salt that crystallizes as a single substance but ionizes as two distinct salts when dissolved, as carnallite, KMgCl 3 ⋅6H 2 O.

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double salt British  

noun

1. a solid solution of two simple salts formed by crystallizing a solution of the two salts Compare complex salt

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double salt Scientific  

1. A salt that crystallizes from an aqueous solution of a mixture of two different ions. The mineral dolomite (CaMg(CO ₃) ₂), for example, is a double salt that crystallizes from a solution containing both calcium and magnesium ions. Double salts exist only as solids.

2. Compare complex salt simple salt

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Etymology

Origin of double salt

First recorded in 1840–50

Example Sentences

See Examples For:

double salt

It said that all 27 trunk routes in the south west of the country would receive double salt treatments at 13:00 and 01:00 throughout the week.

From BBC ● Jan. 5, 2026

The double salt of quinia and urea answers for this purpose, as it is very soluble in water and does not produce inflammation of the connective tissue.

From A System of Practical Medicine by American Authors, Vol. I Volume 1: Pathology and General Diseases by Various

Alum.—This is what is termed a double salt, and is composed of sulphate of alumina and sulphate of potash.

From Museum of Antiquity A Description of Ancient Life by T. L. (Thomas Louis) Haines

The salt of wisdom of the alchemists, a double salt composed of the chlorides of ammonium and mercury.

From Webster's Unabridged Dictionary by Noah Webster

Small double salt and pepper earthen vessel, box-shaped, and decorated.

From Illustrated Catalogue of the Collections Obtained from the Pueblos of Zuñi, New Mexico, and Wolpi, Arizona, in 1881 Third Annual Report of the Bureau of Ethnology to the Secretary of the Smithsonian Institution, 1881-82, Government Printing Office, Washington, 1884, pages 511-594 by James Stevenson