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

The difference between chrome alum and alum crystals is principally that chrome alum has twice the strength of alum crystals, being a double salt, instead of the commercial alum usually sold.

From Harper's Round Table, August 13, 1895 by Various

The greatest part of the formed double salt crystallizes, while the mother-liquid contains chloride of sodium, and some of the double salt.

From A System of Instruction in the Practical Use of the Blowpipe Being A Graduated Course Of Analysis For The Use Of Students And All Those Engaged In The Examination Of Metallic Combinations by Anonymous

The electrolytic separation of cobalt is much more easily and rapidly effected when the potassium oxalate is substituted by the corresponding ammonium salt, as the latter forms a soluble double salt with the cobalt compounds.

From Scientific American Supplement, No. 299, September 24, 1881 by Various

"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