Question

A gaseous mixture contains oxygen and nitrogen in the ratio of 1 :4 by mass. Therefore, the ratio of their number of molecules is:

• A. 1 : 4
• B. 1 : 8
• C. 7 : 32
• D. 3 : 16

Answer 1

The correct option is C 7 : 32

Ans ; C

The ratio of mass of oxygen and nitrogen = $\frac{1}{4}$

Ratio of molecule of oxygen and nitrogen =$\frac{1\ast 14\ast N_a}{16\ast 4\ast N_a}$

= $\frac{7}{32}$