A vessel at `1000 K` contains carbon dioxide with a pressure of `0.5 atm`. Some of the carbon dioxide is converted to carbon monoxide on addition of graphite. Calculate the value of `K_(p)` if total pressure at equilibrium is `0.8 atm`.

Explanation

The reaction taking place is :
`CO_(2) (g) +C(s) hArr 2CO(g)`
Suppose that the decrease in pressure of `CO_(2) (g) ` after taking part in the reaction =p atm.
Then,increase in pressure of `CO(g) =2p atm`
The partial pressure in the equilibrium mixture are :
`CO_(2)(g) +C(s) hArr 2CO (g)`
At eqm. point : (0.5-p) atm " "2ptam
Total pressure `= (0.5 -p + 2p)= (0.5 + p) atm`
But the actual pressure = 0.8 atm (given)
`:. " " 0.5 +p = 0.8 or p = 0.8 -0.5 = 0.3 atm`
According to the equation,
`K_(c) = (P_(CO)^(2)(g))/(P_(CO)^(2))=((0.6 " atm ")xx(0.6 " atm "))/((0.5" atm " -0.3 " atm "))=(0.6 " atm "xx0.6 " atm ")/(0.2" atm ")=1.8 " atm" `