Question

Using standard free energy of formation values given in the introduction, calculate the equilibrium constant kp of the reaction cl2(g)+2no(g)⇌2nocl(g)

Answer 1

d G = 2 (dG NOCl) - 2 (dG NO)

= 2 * 66.08 - 2 * 87.6 = -43.04 kJ /mol

dG = - 2.303 RT log K

-43.04 = - 2.303 RT log K

7.54 = log K

K = 3.42 * 10^7

Kp = k (RT)^dn

d n = 2 - 1 -2 = -1

Kp = (3.42 * 10^7) (8.314 * 298)^-1

Kp = 1.31 * 10^4