Question

A mixture of CO and $C{O}_2$ is found to have a density of 1.5 gm/lt at ${30}^{\circ }$C and 730 torr. The composition of the mixture is in terms of mole percentage is

• A. CO = 27.73 and CO₂ = 72.27
• B. CO = 32.18 and CO₂ = 67.82
• C. CO = 35 and CO₂ = 65
• D. CO = 30 and CO₂ = 70

Answer 1

The correct option is B CO = 32.18 and CO₂ = 67.82

Molecular mass of the mixture M = $\frac{dRT}{P}==\frac{1.5\times 0.0821\times 303\times 760}{730}=38.85gm/mol$
Let the total number of moles be 'x'.
Let 'x' = no. of moles of CO.Then no. of moles of $C{O}_2$ = (1 - x)
Molecular Mass of mixture = x $\times$ 28 + (1 - x)44 = 38.85
$\Rightarrow$ x = 0.3218
% of CO = 32.18 and % $C{O}_2$ = 67.82