Question

At room temperature, the r.m.s. speed of the molecules of certain diatomic gas is found to be 1930 m/s. The gas is

• A. $H_{2}$
• B. $F_{2}$
• C. $O_{2}$
• D. $Cl_{2}$

Answer 1

Answer: (A)

$H_{2}$

Answer 2

$v_{rms} = \sqrt{\frac{3RT}{M}}$Ž $M = \frac{3RT}{v_{rms}^{2}}$\ $M = \frac{3 \times 8.3 \times 300}{(1920)^{2}}$

$= 2 \times 10^{- 3}kg = 2gm$ Ž Gas is hydrogen.