What is the average kinetic energy of the molecules in a gas at 273K?

1 Answer
Jul 31, 2014

The average kinetic energy of the molecules is 5.66 × 10⁻²¹ J.

According to Kinetic Molecular Theory, the average kinetic energy of gas molecules is a function only of temperature.

The formula is

KE=32kT

where T is the Kelvin temperature and k is Boltzmann's constant.

KE=32×1.381×10²³J⋅K¹×273K = 5.66 × 10⁻²¹ J

For a mole of molecules, the average kinetic energy is

5.66×10²¹J1molecule×6.022×10²³molecules1mol = 3.41 ×10³ J/mol = 3.41 kJ/mol