?

AP® Chemistry

Free Version

Upgrade subject to access all content

Moderate

Kinetic Energy and Molecular Velocity Vary With Temperature

APCHEM-O0$MAA

A sample of an ideal gas is cooled from 450 K to 225 K.

Which of the choices below BEST describes the effect on the average molecular kinetic energy, $\overline { KE }$, and the average molecular velocity, $\overline { v } $?

A

Both $\overline { KE } $ and $\overline { v }$ are cut in half.

B

Both $\overline { KE } $ and $\overline { v }$ are reduced by a factor of $\sqrt { 2 } $.

C

$\overline { KE } $ is reduced by a factor of $\sqrt { 2 } $, while $\overline { v }$ is cut in half.

D

$\overline { KE } $ is cut in half, while $\overline { v }$ is reduced by a factor of $\sqrt { 2 } $.