Question 3. A room temperature the r.m.s. velocity of the molecules of a certain diatomic gas is found to be 1930 m/sec. the gas is (a) H² (b) F² (c) O² (d) Cl² Answer
The correct option is B Root means square velocity ν r m s = √ 3 R T M = 1930 m / s (given) ∴ M = 3 R T ( 1930 ) 2 = 3 × 8.31 × 300 1930 × 1930 = 2 × 10 − 3 k g = 2 g m i.e. the gas is hydrogen
