Question

Oxygen and hydrogen are kept under the same temperature and pressure. Oxygen molecule is 16 times more massive than hydrogen one. The average speed of molecule of oxygen is:______.

Answer 1

The average speed of molecule of oxygen is one-fourth of the speed of the hydrogen molecule.

Step-by-step explanation:

The kinetic energy of gas molecule is given by following equation:

`K.E = (3)/(2) KT`

Since the temperature (T) is constant for both molecules. Therefore, there kinetic energies will also be the same. Therefore,

`K.E_(O_2) = K.E_(H_2)\\(1)/(2)m_(O_2)v_(O_2)^2 = (1)/(2)m_(H_2)v_(H_2)^2 \\\\but,\\\\m_(O_2) = 16m_(H_2)\\\\therefore,\\16 m_(H_2)v_(O_2)^2 = m_(H_2)v_(H_2)^2\\\\\\taking square root on both sides, we get:\\4v_(O_2) = v_(H_2)\\\\v_(O_2) = (v_(H_2))/(4)`

The average speed of molecule of oxygen is one-fourth of the speed of the hydrogen molecule.