ChemistryNEET 2024Law of mass action, Kc and Kp, Le Chatelier

Equilibrium

In which of the following equilibria are $K_{p}$ and $K_{c}$ not equal?

A. $H_{2} (g) + I_{2} (g) ⇌ 2HI (g)$
B. $CO (g) + H_{2} O (g) ⇌ C O_{2} (g) + H_{2} (g)$
C. $2BrCl (g) ⇌ B r_{2} (g) + C l_{2} (g)$
D. $PC l_{5} (g) ⇌ PC l_{3} (g) + C l_{2} (g)$ ✓

Solution

$K_{p} = K_{c} (R T)^{Δ n_{g}}$ ; they are equal only when $Δ n_{g} = 0$ . For $PC l_{5} ⇌ PC l_{3} + C l_{2}$ , $Δ n_{g} = 2 - 1 = 1$ , so $K_{p} \neq = K_{c}$ . The other three have equal moles of gas on both sides.

Save for spaced revision (free account)

Equilibrium

More from this chapter in past papers