Equilibria

Question 1

For the general reaction aA + bB ⇌ dD + eE, express the equilibrium constant Kc.

Answer 1

Kc = [D]ᵈ[E]ᵉ/[A]ᵅ[B]ᵇ

Question 2

Why is Kc not affected by changes in pressure?

Answer 2

Because it is always measured at dynamic equilibrium; an initial increase in pressure shifts the equilibrium to the side with fewer moles, this decrease in pressure shifts the equilibrium to the side with more moles; eventually dynamic equilibrium is restored, hence Kc is restored

Question 3

Why is Kc not affected by changes in concentration?

Answer 3

Because it is always measured at dynamic equilibrium; the equilibrium shifts to counteract a changes in concentration, until the dynamic equilibrium has been restored, hence Kc is restored

Question 4

If more product is formed, the value of Kc _________.

Answer 4

increases

Question 5

What effect do catalysts have on Kc?

Answer 5

Catalysts have no effect on the position of equilibrium, but their presence allows dynamic equilibrium to be reached faster