Equilibrium Constant of a Heterogeneous Reaction

1. Jul 11, 2016

Saracen Rue

1. The problem statement, all variables and given/known data
Write an expression for Kc for the following at equilibrium;
CaCO3(s) + CO2(g) + H2O(l) ⇔ Ca2+(aq) + 2HCO3-(aq)

2. Relevant equations
K = [products]^(coefficients)/[products]^(coefficients)

3. The attempt at a solution
I know that pure solid and liquid substances should be set to 1 when calculating the equilibrium constant. However, I haven't encounter an equation before where both aqueous and gaseous substances are present. Does this effect how I should set up the equation for the equilibrium constant at all? Thank you for your time

2. Jul 12, 2016

Staff: Mentor

You should use a partial pressure of the gas.