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Properties of Matter Element Card 3, Lesson 21



Melting point

839° C

Boiling point

1484° C


1.54 g/cm³


Calcium is dull gray, but it is shiny when scratched.

Other physical properties

Calcium is an excellent conductor of electricity. It is very soft and easily scratched.

Chemical properties

Calcium reacts rapidly with air to form a coating of gray oxide, and it burns with a red flame.


Compounds of calcium are white in color. One compound is calcium carbonate, which makes up limestone (used in cement manufacture).




Calcium is the fifth most abundant element in Earth's crust.

Calcium and calcium oxide both react with water to form calcium hydroxide. When calcium reacts with water, hydrogen gas is released.


A dinosaur skeleton on display

Calcium compounds, particularly calcium phosphate, are important components of teeth and bones.

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