Question

Which of the following is true for a chemical reaction at equilibrium?

a. only the forward reaction stops
b. only the reverse reaction stops
c. both the forward and reverse reactions stop
d. the rate constants for reverse and forward reactions are equal
e. the rates of reverse and forward reactions are equal

Answer 1

In reality, the forward and reverse reactions never stop in the system. Their rates are non-zero, but equal. The ratio of the rate constants for forward and reverse reactions is the equilibrium constant:

$K_{eq} = \frac{k_{forward}}{k_{reverse}}$ .

For a dynamic chemical equilibrium, the rates of reverse and forward reactions are equal.

Answer: e. the rates of reverse and forward reactions are equal.