Question

Which statement is true of a reversible reaction at equilibrium? A. The concentration of reactants is less than the concentration of products. B. The concentration of reactants and the concentration of products are equal. C. The concentration of reactants is greater than the concentration of products. D. The concentration of reactants and the concentration of products are constant. E. The concentration of reactants is decreasing and the concentration of products is increasing.

Answer 1

Answer: Option (D) is the correct answer.

Step-by-step explanation:

An equilibrium reaction is defined as the reaction in which concentration of both reactants and products are constant.

For example,
`N_(2)(g) + 3H_(2)(g) \rightleftharpoons 2NH_(3)(g)`

In a dynamic equilibrium, rate of forward and backward reaction are continuous.

So, rate for this reaction will be as follows.

Rate =
`([NH_(3)]^(2))/([N_(2)][H_(2)]^(3))`

When rate of forward reaction is equal to rate of backward reaction then it is known as reversible reaction.

Thus, we can conclude that the statement concentration of reactants and the concentration of products are constant, is true of a reversible reaction at equilibrium.

Answer 2

Answer: -

D. The concentration of reactants and the concentration of products are constant.

Explanation: -

In the case of a reversible reaction at equilibrium,

The rate of forward reaction is equal to the rate of backward reaction.

So, the amount of product being formed is the same as the amount of reactant being formed in unit time.

Thus the concentration of reactants and the concentration of products are constant for a reversible reaction at equilibrium.