cobalt chloride


: a chloride of cobalt
especially : the dichloride CoCl2 that is blue when dehydrated, turns red in the presence of moisture, and is used to indicate humidity

Example Sentences

Recent Examples on the Web Some have additives in the form of cobalt chloride or methyl violet. Jeff Lowenfels, Anchorage Daily News, 3 Dec. 2020 The silica used incorporates cobalt chloride, which helps to retain both the shape and color of the flowers. Julia Sayers,, 7 Mar. 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'cobalt chloride.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1869, in the meaning defined above

Time Traveler
The first known use of cobalt chloride was in 1869

Dictionary Entries Near cobalt chloride

Cite this Entry

“Cobalt chloride.” Dictionary, Merriam-Webster, Accessed 8 Jun. 2023.

Kids Definition

cobalt chloride

: a chloride of cobalt
especially : one that has two atoms of chlorine per molecule, is blue when dry and deep pink when combined with water, and is used to indicate humidity

More from Merriam-Webster on cobalt chloride

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