A student writes the following explanation: "When a gas sample in a sealed
CHEMISTRY · Single correct · AP · Chemistry · Properties of Substances and Mixtures · Properties of Substances and Mixtures
Problem
A student writes the following explanation:
"When a gas sample in a sealed, rigid container is cooled, its pressure decreases because the gas particles lose mass and collide with the container walls less often."
Which revision best corrects the error in the student’s statement?
(a) Replace "collide with the container walls less often" with "collide with each other more often," because pressure depends mainly on intermolecular collisions.
(b) Replace "sealed" with "open," because the pressure change occurs only when particles can leave the container.
(c) Replace "lose mass" with "move more slowly," because particle mass remains constant while speed decreases.
(d) Replace "rigid" with "flexible," because the container walls must contract for the pressure to decrease.