Question

the diagram shows two identical, rigid containers with different amounts of he(g) at the same temperature. which of the following statements best explains a higher pressure in container y compared with container x?
a there are more collisions between gas particles in container y.
b there are more collisions between gas particles and the walls of container y.
c the gas particles in container y have a greater average kinetic energy.
d the gas particles in container y have a higher average speed.

Explanation:

• Option A: Collisions between gas particles do not contribute to pressure. Pressure is due to gas - particle - wall collisions.
• Option B: According to the kinetic - molecular theory of gases, pressure is caused by the collision of gas particles with the walls of the container. Since container Y has more gas particles (higher number density as the containers are identical in volume), there are more frequent collisions between gas particles and the walls of container Y, resulting in higher pressure.
• Option C: At the same temperature, the average kinetic energy of gas particles (\(K.E.=\frac{3}{2}kT\), where \(k\) is the Boltzmann constant and \(T\) is the temperature) is the same for both containers.
• Option D: At the same temperature, the average speed of gas particles (\(v_{rms}=\sqrt{\frac{3RT}{M}}\), where \(R\) is the gas constant, \(T\) is the temperature, and \(M\) is the molar mass) is the same for both containers as the gas is He (same \(M\)) and \(T\) is the same.

Answer:

B. There are more collisions between gas particles and the walls of container Y.