water of hydration

American  

noun

Chemistry.

1. the portion of a hydrate that is represented as, or can be expelled as, water: now usually regarded as being in true molecular combination with the other atoms of the compound, and not existing in the compound as water.

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water of hydration Scientific  

1. Water that is chemically combined with other molecules to form a hydrate mineral and that is easily removed through heating.

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Etymology

Origin of water of hydration

First recorded in 1885–90

Example Sentences

Heating a sample of Na2CO3⋅xH2O weighing 4.640 g until the removal of the water of hydration leaves 1.720 g of anhydrous Na2CO3.

From Textbooks • Feb. 14, 2019

In other cases, the precipitates are hydrated oxides composed of the metal ion, oxide ions, and water of hydration:

From Textbooks • Feb. 14, 2019

In enamelling it cannot be used; the colour, depending on the water of hydration, being destroyed by a strong heat.

From Field's Chromatography or Treatise on Colours and Pigments as Used by Artists by Salter, Thomas

Conversely, if only 3/4 of the water of hydration be expelled during the baking of gypsum, the material obtained should hydrate itself more slowly.

From Scientific American Supplement, No. 794, March 21, 1891 by Various

The hydrate of baryta melts by a low red heat without losing its water of hydration.

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