Question

Vapour density of a metal chloride is $66.$ Its oxide contains $53\%$ metal. The atomic weight of the metal is

• A. 21
• B. 54
• C. 27.06
• D. 2.086

Answer 1

The correct option is C 27.06

VD of metal chloride $=66$

To find, the atomic mass of metal.

Let the weight of metal oxide $=100gm$

weight of metal $=53gm$

weight of oxygen $=47gm$

Equivalent weight of metal$=\frac{\text{Weight of metal}}{\text{Weight of oxygen}}\times 8$

$=\frac{53}{47}\times 8$

$=9.02$

Valency $=\frac{2\times VD}{E+35.5}$

$=\frac{2\times 66}{9.02+35.5}$

$=2.96\sim 3$

Atomic weight $=$ Equivalent weight $\times$ valency

$=9.02\times 3$

Atomic weight $=27.06$

Hence, the correct option is $\text{C}$