CHEMISTRY · Single correct · A Level · Chemistry · Amount of substance · Amount of substance
Problem
A sealed container of neon gas and a separate, identical container of krypton gas are both at the same temperature. A tiny pinhole is opened in each container. Which statement correctly compares the initial rates at which the two gases escape through the pinholes?
(a) Both gases escape at the same rate because their average kinetic energy is the same at a given temperature.
(b) Krypton escapes faster because its greater molar mass gives its atoms more momentum to pass through the pinhole.
(c) Neon escapes faster because its atoms are less massive than krypton's.
(d) Neon escapes slower because its atoms have lower average speed at the same temperature.