Equimolal solutions of KCI and compound X in water show depression in freezing point in the ratio of 4:1 . Assuming KCI to be completely ionized, the compound X in solution must

KCI              and      X (p moles)                (p moles) ∆Tf(KCI)=iKfm=2Kfm ∆Tf(X)=iKf.m=14(2Kfm)⇒i=12<1 2X       ⇌        X2   1                        0 1-α                  α/2 i=1-α+α2=1-α2=12⇒α=100% 3X          ⇌         X3 1                            0 1-α                      α/3 i=1-α+α3=1-2α3=12⇒α=34=75%