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Question
A compound 'X' consists of 4.8% of C and 95.2% of Br by mass.
If the vapour density of the compound is 252, what is the molecular formula of the compound?
Solution
Vapour density = 252
Empirical formula mass = 12 + 3 x 80 = 252
Molecular mass = 2 x Vapour density
= 2 x 252 = 504
Now, n= Molecular mass / Empirical Formula Mass
= 504/252 = 2
Molecular formula = n x Empirical Formula
= 2 x CBr3 = C2Br6
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