Answer: Avogadro number.
- A Avogadro number
- B the Boltzmann constant
- C the gas volume
- D the molar mass
Correct answer: A. Avogadro number
Explanation: k = R/N<sub>A</sub>, so it is the gas constant per molecule.
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.