Answer: vrms = √(3RT/M).
- A vrms = √(2RT/M)
- B vrms = √(3RT/M)
- C vrms = √(8RT/πM)
- D vrms = RT/M
Correct answer: B. vrms = √(3RT/M)
Explanation: vrms = √(3RT/M), where R is the gas constant, T is absolute temperature, and M is the molar mass.
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.