Answer: the container walls.
- A the container walls
- B the distant planets
- C the laboratory floor
- D the incident light
Correct answer: A. the container walls
Explanation: Gas pressure is caused by molecules striking the container walls.
Not all gas molecules move at the same speed - the Maxwell-Boltzmann distribution shows the spread, with the most probable speed vp slightly less than the average vavg, which is slightly less than the root-mean-square speed vrms used in the pressure formula.
Concept context
Kinetic theory of gases connects molecular motion to pressure and temperature, explaining gas laws, specific heats, and molecular speeds.