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

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

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 Haines, T. L. (Thomas Louis)

By leaving the hot saturated solution to cool it does not cloud, but the double salt separates pretty rapidly in the form of plates.

From Scientific American Supplement, No. 324, March 18, 1882 by Various

It forms a very sensitive double salt with ammonia and several other metals.

From Nitro-Explosives: A Practical Treatise by Sanford, P. Gerald (Percy Gerald)

The double salt is non-toxic, though sometimes in exceedingly weak patients it produces vertigo.

From The Medicinal Plants of the Philippines by Thomas, Jerome Beers