Question

Which of the following represents the chemical formula of Calcium Carbonate?

• A. Endothermic
• B. Exothermic
• C. Combination
• D. Synthesis

Answer 1

The correct option is A

Endothermic

The given compound contains ions as its constituents.

The Calcium ion is $C{a}^{2+}$ and has a valency +2.

The Carbonate ion has the formula ${CO}_3^{-2}$ and has a valency -2.

By crossing over the valencies and balancing charge,

we get the formula as $Ca{CO}_3$.