For the equilibrium described by:

2 HgO (s) $⇄$ 2 Hg (l) + O₂ (g) [K_P = 12.0 atm at 850 K]
1) Find the relation between K_P and K_C.
2) Find the value of K_C at this temperature.

Question

For the equilibrium described by:

2 HgO (s)

⇄

2 Hg (l) + O₂ (g) [K_P = 12.0 atm at 850 K]

1) Find the relation between K_P and K_C.

2) Find the value of K_C at this temperature.

| General Chemistry 2

Accepted Answer

1) K_P = P_O2 and K_C = [O₂]

⇒ K_P = K_C RT

2) K_C =

\frac{K_{P}}{RT}

with K_P in Pa ⇒ 12.0 atm = 12.2 x 10⁶ Pa

R = 8.314 J.mol^-1.K^-1

T in K

K_C =

\frac{12.2 \times 10^{6}}{8.314 \times 850}

= 1.73 x 10³ mol.L^-1

Exercise 4 | Chemical Equilibrium