2NO(g)+Cl2(g)⇌2NOCl
t=0 0.02 0 0
teq. 0.02×99100 p 0.02×1100
Kp=[pNOCl]2[pNO]2[ClCl2]=(0.02×0.01)2(0.02×0.01)2×p=10−3
p=0.0102 atm
PV=nRT
0.102×V=nRT...(i)
1×V=0.2×R×T...(ii)
From eqs (i) and (ii), n=0.0204 (no. of moles of Cl at equilibrium)
Pressure of Cl2 involved in reaction
=12× pressure of NOCl
=12×0.02100=0.0001atm
PV=nRT
0.0001×V−nRT.........(iii)
From eqs. (ii) and (iii), n=2×10−5 (moles of Cl2 involved in reaction)
Initial moles of Cl2 taken=0.0204+2×10−5=0.0242