Question

At a certain temperature and total pressure of 10⁵ Pa, iodine vapours contain 40% by volume of iodine atoms in the equilibrium I₂ (g) ⇌ 2I(g). Calculate K_P for the equilibrium.

Answer 1

According to available data:

Total pressure of equilibrium mixture = 10⁵ Pa 

Partial pressure of iodine atoms (I) = 40/100 x (10⁵ Pa) = 0.4 x 10⁵ Pa

Partial pressure of iodine molecules (I₂) = 60/100 x (10⁵ Pa) = 0.6 X 10⁵ Pa