Question

The density of water is $1000$ kg $m^{-3}$. The density of water vapour at ${100}^{o}C$ and $1$ atm pressure is $0.6$ kg $m^{-3}$. What is the ratio(or refraction) of the molecular volume to the total volume occupied by the water vapour under the above conditions of temperature and pressure?

• A. $6\times {10}^{-4}$
• B. $3\times {10}^{-4}$
• C. $12\times {10}^{-4}$
• D. $6\times {10}^{-3}$

Answer 1

The correct option is A $6\times {10}^{-4}$

$\frac{v_{\text{vapour}}}{v_{\text{water}}}=\frac{\frac{M}{0.6}}{\frac{m}{1000}}=\frac{\text{5000}}{3}$

$\frac{v_{\text{water}}}{v_{\text{vapour}}}=0.6\times {10}^{-3}=6\times {10}^{-4}$

Answer: - (A)