Which of the following statements about an equilibrium system is correct?

A.

Forward and backward reactions occur at the same rate

B.

The concentrations of reactants must equal that of the products

C.

The concentrations of, reactants and products can be changed by adding a catalyst,

D.

The concentrations of reactants and products are not affected by a change in temperature

Correct answer is A

Equilibrium is a state of a system where there is no observable change in the properties of the system with respect to time