Question

For the reaction: P⇋Q+ R. Initially, 2 moles of P was taken. Up to equilibrium 0.5 moles of P was dissociated. What would be the degree of dissociation?

A. 0.5
B. 1
C. 0.25
D. 4.2

Answer 1

The degree of dissociation is the fraction of the initial quantity of a substance that has dissociated at equilibrium. In this case, with 0.5 moles of P dissociated from the initial 2 moles, the degree of dissociation is 0.25 or 25%. The correct option is (C).

Step-by-step explanation:

The question asks us to calculate the degree of dissociation for the reaction P ⇄ Q + R. The degree of dissociation is defined as the fraction of the original substance that has dissociated at equilibrium. To find this, we divide the number of moles dissociated by the initial number of moles.

Initially, there were 2 moles of P and at equilibrium, 0.5 moles of P had dissociated. Therefore, the degree of dissociation (α) can be calculated using the formula:

α = Moles dissociated at equilibrium / Initial moles of P
= 0.5 moles / 2 moles
= 0.25 or 25%

Hence, the degree of dissociation is 0.25, which corresponds to answer choice C.