# What is the reaction of the decomposition of calcium carbonate?

Calcium carbonate will decompose to form carbon dioxide and calcium oxide.

Carbonate compounds will decompose when heated.

Here is the balanced equation for this reaction:
$C a C {O}_{3}$(s) -> CaO(s) + $C {O}_{2}$(g)

Calcium carbonate has a 1:1 ratio because calcium forms a +2 ion and carbonate has a -2 charge.

Calcium oxide must have the formula CaO because calcium forms an ion with a +2 charge and oxide has a -2 charge.