Question

At 298 K the average kinetic energy is the same for H2, He, and N2. The gas with the highest average velocity is:

A) H2
B) He
C) N2
D) All have the same average velocity

And Why ? eplain if possible please

Answer 1

answer : A ) H2

explanation : average kinetic energy is same for all molecules at constant temeprature. because the formula for average kinetic energy = 3/2 * R * T

avarage kinetic energy depends on temperature not on molar mass of anything . so it is same for all gases

but average velocity depends on molar mass of the molecule .

average velocity formula =

here M = molar mass mass of the gas. molar mass increases average velocity decreases .least molar mass will be highest average velocity .

here given H2 molar mass 2 g / mol . He molar mass 4 g / mol and N2 molar mass 28 g / mol.

so average velocity order : H2 > He > N2