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Grade 12Physical Chemistry

At 250°c;the vapour density of pcl5 is Y(at equilibrium)and molar mass is Q(intially) Its degree of dissociation is then equal to-

Profile image of Rajvishnu
8 Years agoGrade 12
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1 Answer

Profile image of Arun
8 Years ago
 
The Reaction for the PCl5 is:
PCl5 ====>     PCl3    + Cl2
n = 1 + 1 = 2
Now the degree of dissociation related o the theoretical mass and the observed mass is:
a = (Mth – Mobs.)/Mth.(n -1)
a = (208.24 – 200)/(208.4*(2-1)) => 0.039 or 3.9% disscocitaion.