alkaline earth

American  

noun

Chemistry.

1. any of the oxides of barium, radium, strontium, calcium, and, sometimes, magnesium.

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alkaline earth British  

noun

1. Also called: alkaline earth metal.   alkaline earth element.  any of the divalent electropositive metals beryllium, magnesium, calcium, strontium, barium, and radium, belonging to group 2A of the periodic table

2. an oxide of one of the alkaline earth metals

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Etymology

Origin of alkaline earth

First recorded in 1810–20

Example Sentences

The only result that popped up pertained to chemistry: specifically, to the periodic table and the atomic numbers of the alkaline earth metals.

From New York Times • May 21, 2023

Although they are insoluble in pure water, alkaline earth carbonates dissolve readily in water containing carbon dioxide because hydrogen carbonate salts form.

From Textbooks • Feb. 14, 2019

The higher ionization energy makes the alkaline earth metals less reactive than the alkali metals; however, they are still very reactive elements.

From Textbooks • Feb. 14, 2019

Unlike most salts of the alkali metals, many of the common salts of the alkaline earth metals are insoluble in water because of the high lattice energies of these compounds, containing a divalent metal ion.

From Textbooks • Feb. 14, 2019

It is a member of the alkaline earth group of elements.

From The Gutenberg Webster's Unabridged Dictionary Section C by Project Gutenberg