Total pressure of equilibrium mixture = 105 Pa
Partial pressure of iodine atoms (I) = \(\frac{40}{100}\) x (105 Pa) = 0.4 x 105 Pa
Partial pressure of iodine molecules (I2)
\(\frac{60}{100}\) x (105 Pa) = 0.6 x 105 Pa
I2(g) (0.6 x 105 Pa) ⇌ 2I(g) (0.4 x 105 Pa)
KP = \(\frac{p^2I}{pI_2}\) = \(\frac{(0.4 \times 10^5\, Pa)^2}{(0.6 \times 10^5\, Pa)}\) = 2.67 x 104 Pa