JEE Main202312 Apr 2023Morning ShiftPhysicsKinetic Theory of GasesActual
If the r.m.s speed of chlorine molecule is 490 m s - 1 at 27 o C , the r.m.s speed of argon molecules at the same temperature will be (Atomic mass of argon = 39 . 9 u , molecular mass of chlorine = 70 . 9 u )
Options
- A551 . 7   m   s - 1
- B651 . 7   m   s - 1
- C451 . 7   m   s - 1
- D751 . 7   m   s - 1
Correct answer
B. 651 . 7   m   s - 1
Step-by-step solution
The formula to calculate the rms speed of the argon molecules is given by v A r = 3 R T M A r       . . . 1 The formula to calculate the rms speed of chlorine molecule is given by v C l = 3 R T M C l       . . . 2 Divide equation (1) by equation (2) and simplify to obtain the required ratio. v Ar v Cl = M Cl M Ar       . . . 3 Substitute the values of the known parameters into equation (3) and solve to calculate the required value. v Ar 490   m   s - 1 = 71 40