Question

The ratio of masses of oxygen and nitrogen in a particular gaseous mixture is $1:4$. The ratio of number of their molecule is: $x:y$. Find the value of $x+y$

Answer 1

Number of moles of $O_2=\frac{w}{32}$
Number of moles of $N_2=\frac{4w}{28}=\frac{w}{7}$
$\therefore \text{Ratio}=\frac{w}{32}:\frac{w}{7}=7:32$
$x+y=32+7=39$