Question

A metal Z forms a volatile chloride containing 65.5% chlorine. If the density of the chloride relative to hydrogen is 162.5,find the molecular formula of the metal chloride(Z=56, Cl=35.5)

Answer 1

Dear Student,
% of Cl= 65.5%
Percentage of metal= 100- 65.5 = 34.5 %

Element	percentage	atomic mass	relative number of atoms	simplest ratio
M	34.5%	56	34.5/56=0.61	0.61/0.61= 1
Cl	65.5%	35.5	65.5/35.5=1.84	1.84/0.62=3

So the empirical formula of chloride= MCl_​3
empirical formula mass=162.5 gm
Vapour density= 162.5
molecular mass = 2(VD)= 325
$n=\frac{empiricalmass}{molecularmass}=2$
So. the Molecular formula = (MCl₃)₂= M₂Cl₆
Regards!