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

"Citrate of iron and ammonium" is a double salt formed of ferric citrate and citrate of ammonium, and comes in brown shining leaflets.

From Harper's Round Table, August 27, 1895 by Various

It yields a crystalline hydrochloride and double salt with gold chloride and has given it the formula C_5H_11NO_2.

From The Vitamine Manual by Eddy, Walter H.

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

So far, however, as the application to dyeing is concerned, it is unnecessary to prove that the ancients used our double salt alum.

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