Question

At constant temperature and pressure, the rate of diffusion of the gases is inversely proportional to the square root of their:

• A. volume
• B. density
• C. number of moles
• D. concentration

Answer 1

The correct option is B density

Rate of diffusion $\propto \sqrt{\frac{1}{M}}$ $M=$ Molecular mass.

We know $PV=nRT⟹PV=\frac{m}{M}RTPM=\frac{m}{V}RT⟹PM=dRTd=density.$

$M=\frac{dRT}{P}$

At constant temperature and pressure, $M\propto density.$

So, rate of diffusion $\propto \frac{1}{\sqrt{d}}$