solid (NH4)2CO3 is placed in an evacuated container at 115C. When equilibrium is reached the total pressure inside the vessel is 0.473 atm. Some solid remain in the vessel at equilibrium. Calculate Kp.

Answer 1

..........(NH4)2CO3 ==> 2NH3 + CO2 + H2O
I..........solid.........0......0.....0
C..........solid........2p......p.....p
E..........solid........2p......p.....p

Kp = p^2NH3 * pCO2 * pH2O
Ptotal = pNH3 + pCO2 + pH2O
0.473 = 2p + p + p = 4p
Solve for p and substitute into Kp expression and solve for Kp.