Page 20 - Curriculum Visions Dynamic Book

Calcium oxide
Calcium oxide, also known as quicklime, is a major constituent of every bag of cement you buy.
If limestone (calcium carbonate) is heated in a kiln, it will decompose to produce carbon dioxide gas and create a white solid of calcium oxide. A laboratory demonstration of the effect is shown here.
 The apparatus below shows how a small block of calcium carbonate (limestone) can be made into calcium oxide in the laboratory. It consists of an iron cylinder
(the kiln) with a tray on which the limestone rests.
 A cover is put over
the kiln and the limestone heated using a Bunsen burner. The limestone decomposes to form a white solid, called calcium oxide or quicklime, and gives off carbon dioxide gas. In the picture you can see the limestone glowing a yellow–red colour.
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