Dear student,
Please find the solution to your problem below.
CO2 + C → 2CO
initial presasure = 0.5 atm
final pressure on addition of graphite
CO2 = 0.5 – x
CO = 2x
total pressure at equilibrium = 0.5 + x
but the total pressure at equilibrium = 0.8 atm
0.5 + x = 0.8 atm
x = 0.3 atm
Hence, at equilibrium pressure of CO2 = 0.2 atm and CO = 0.6 atm
the value of reaction constant,K=[CO]2/[CO2] = 0.62/0.3 = 1.2
Thanks and regards,
Kushagra