Question

Which gas molecules have the highest average kinetic energy at a given temperature?

Answer 1

Answer:

• All the gas molecules have the same average kinetic energy at a given temperature, under ideal gas assumption.

Explanation:

The three molecules, HBr, NO₂, and C₂H₆, such as any other gas molecule, under gas ideal assumption, have the same average kinetic energy at a given temperature.

The temperature is a measure of the kinetic energy of the of the particles (atoms or molecules) of a gas matter.

At a given temperature, all the gases have the same average kinetic energy of all gases.

That does not mean that all the particles have the same kinetic energy. This principle is not valid for individual particles. Different particles of a same (or differfen)t gas will have different speeds and consequently their individual kinetic energy will vary.

This principle is derived from the molecular kinetic theory and the mathematical expression for the kinetic energy in terms of temperature is:

• $KE_{avg}=\frac{3}{2}K_BT$

Where:

• KE (avg) = average kinetic energy

• KB = Boltzman constant
• T = absolute temperature