Vapour density of PCl5 is 104.25 at T degree C. Then degree of dissociation of PCl5 is?

Dear Kashi Eklarkar,

                      PCl₅ <----> PCl₃ + Cl₂
Initial mole    1                 -            -    
Moles at eqm  1-x           x            x 
Total mole at equilibrium = 1-x+x = 1+x

VD (mix) = VD (theoretical) / total mole
104.25  = 104.25 / 1+ x
1+x =1
x =1
In terms of % = 100 %
Thus its 100 % dissociation.