AB2(g) ⇌A(g) +2B(g)
Initial mole 1 0 0
At eq. 1−x x 2x
At equilibrium,
nT=PVRTnT=1.9×250.08206×300=1.93Total number of moles at equilibrium:nT=1−x+x+2x=1+2x1+2x=1.93∴ x=0.465
KP=PAP2BPAB2PA=XAPtotalKP=(0.4651.93×1.9)(0.931.93×1.9)2(0.5351.93×1.9)∴ KP=73×10−2 atm2