Question

At 1127 and 1 atm pressure, a gaseous mixture of CO and CO₂ in equilibrium with solid carbon has 90.55% CO by mass

C(s) + CO₂(g) ⇌ 2CO(g)

Calculate K_c for this reaction at the above temperature.

Answer 1

Calculation K_p for the reaction:

Let the total mass of the gaseous mixture = 100 g

Mass of CO in the mixture = 90.55 g

Mass of CO₂ in the mixture = (100 - 90.55) = 9.45 g

No. of moles of CO = \(\frac{90.55}{(28\,g\,mol^{-1})}\) = 3.234 mol

No. of moles CO₂ = \(\frac{90.55}{(44\,g\,mol^{-1})}\) = 0.215 mol

pCO in the mixture = \(\frac{(3.34 \,mol)}{(3.23-0.215)}\) x 1 atm

= \(\bigg[\frac{3.234\,mol}{3.449\,mol}\bigg]\) x 1 atm = 0.938 atm

pCO₂ in the mixture = \(\frac{(0.215\,mol)}{(3.449\,mol)}\) x 1 atm

= 0.062 atm

Calculation of K_C for the reaction