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

`CO_(2)(g)+C(s)hArr2CO(g)`
`{:(Initial,,0.5 "atm",,0 "atm"),(At equilibrium,,(0.5-x),,2x "atm"):}`
At equilibrium, the total pressure is `0.8 "atm"`.
`p_("total")=p_(CO_(2))+p_(CO)`
`0.8=(0.5-x)+2x=0.5+x`
or `x=0.3 "atm"`
Applying the law of mass action
`K_(p)=((p_(CO))^(2))/(p_(CO_(2)))=((2xx0.3)^(3))/0.2=0.36/0.2=1.8 "atm"`