Calcium oxide and carbon dioxide combine to form calcium carbonate in the reversible reaction:

Question

CaO + CO2 ⇌ CaCO3

When the reaction is at dynamic equilibrium, which statement must be true?

(1 point)
Responses

Calcium carbonate and calcium oxide are formed at the same rate.
Calcium carbonate and calcium oxide are formed at the same rate.

The concentration of calcium carbonate is increasing.
The concentration of calcium carbonate is increasing.

The forward and reverse reactions have stopped.
The forward and reverse reactions have stopped.

The reaction has run out of carbon dioxide or calcium oxide.

Answer 1

When the reaction is at dynamic equilibrium, the correct statement must be:

Calcium carbonate and calcium oxide are formed at the same rate.

At dynamic equilibrium, the rates of the forward reaction (formation of calcium carbonate from calcium oxide and carbon dioxide) and the reverse reaction (decomposition of calcium carbonate into calcium oxide and carbon dioxide) are equal. This means that the concentration of reactants and products remains constant over time, but the reactions themselves are still occurring.