PCl5 dissociates to the extent of 30% at a total equilibrium pressure of 1.5 atm, PCl5(g) PCl3(g) + Cl2(g). Calculate K_p in atm, to two decimal places.

JEE Main levelNumerical answerDifficulty 2 of 3ce020

$PCl X_{5}$ dissociates to the extent of 30% at a total equilibrium pressure of 1.5 atm, $PCl X_{5} (g) PCl X_{3} (g) + Cl X_{2} (g)$ . Calculate $K_{p}$ in atm, to two decimal places.

Numerical answer type, answer in atm, tolerance 0.005.

With initial 1 mol, total moles

= 1 + α

and

K_{p} = α^{2} P / (1 - α^{2})

. Then

K_{p} = (0.09) (1.5) /0.91 = 0.1484 atm