# How would you calculate the value of K_p for the equation C(s) + CO_2(g) leftrightarrow 2CO(g)?

For $C \left(s\right) + C {O}_{2} \left(g\right) r i g h t \le f t h a r p \infty n s 2 C O$;
K_p=p_"carbon monoxide"^2/(p_"carbon dioxide")
And thus ${K}_{p}$ is simply the quotient of the partial pressures, modified by their stoichiometric coefficient. Carbon does not appear in the expression as a solid does not exert a partial pressure, nor does it express a concentration in ${K}_{c}$.