X⇌Y+Z.........(1) A ⇌ 2B..............(2) X⇌Y+Z 1  0  0  Initially 1-α α α  at equilibrium Total no.of moles at equilibrium=1−α+2α =1+α Similarly A⇌2B 1,  0 Initially when t=0 1-α 2α at equilibrium Total no.of moles at equilibrium=1−α+2α 1=1+α