at certain temperature and total pressure of 1 atm A2 vapours contains 20% by volume of A atoms A2(g)→2A(g) the kp of the reaction is

Question

At a certain temperature and total pressure of 1 atm , A ₂ vapour contains 20% by volume of A atoms A₂ (g) -----> 2A(g). The KP of the reaction is :

Answer 1

Total Pressure,P = 1atm = 10⁵ Pa
As 20 % molecules are A atoms 80% are A₂ molecules.
Partial pressure of A(g), p_A = 0.2 x 10⁵ Pa
Partial pressure of A₂ (g), p_A2 =0.8 x 10⁵ Pa