In case of heterogeneous equilibrium. The achive mass of solid is unit so not consider in the expression of KpandKc
NH2COONH4(s)⇌2NH3(g)+CO2(g)
At equilibrium ⇒ 2 p and p will be partial pressures of ammonia and carbon dioxide gas respectively.
KP=[PNH3]2[PCO2]=[2P]2[P]=4P3
4P3=2⋅9×10−5atm3
P3=0⋅725×10−5atm3=7⋅25×10−6atm3
P=37⋅25×10−6=1⋅94×10−2atm
ΣP=(PTotal)equilibrium=2P+P=3P
=3×1⋅94×10−2atm
=5⋅82×10−2atm