Answer to Question #29601 in Inorganic Chemistry for Vicky Uzuegbu

Question

1) Hydrogen iodide 0.2 moles each of H2 and I2 into a 1litre flask. Calculate the equilibrium contact value (Kc) for the reaction when a) 0.0z
7 moles per litre eaach of H2 and I2 was present at equilibrium. B) 0.20 moles per litre each of H2 and I2 had each at the time equilibrium was established.

Answer 1

The reaction is:
H₂ + I₂ = 2HI

A)
The concentrations are:
C(H₂) = 7 / 1 = 7 M
C(I₂) = 7/ 1 = 7 M
C(HI) = 7*2 / 1 = 14 M
K_c = [HI]²/[H₂][I₂]
so the equilibrium contact value will be
K_c = 14² / 7*7 = 4

B)
The concentrations are:
C(H₂) = 0.2 / 1 = 0.2 M
C(I₂) = 0.2 / 1 = 0.2 M
C(HI) = 0.2 *2 / 1 = 0.4 M
K_c = [HI]²/[H₂][I₂]
so the equilibrium contact value will be
K_c = 0.4² / 0.2*0.2 = 4
Answer: 4