Two students discuss the factors influencing the speed of gas molecules. Student 1: The speed of gas molecules is determined solely by the thermal energy (temperature) of the system. As temperature increases, the kinetic energy of all gas molecules increases uniformly, regardless of the gas's identity or molar mass. Student 2: The speed of gas molecules depends on both temperature and the molar mass of the gas. At a constant temperature, lighter molecules (like Helium) travel significantly faster than heavier molecules (like Xenon) because kinetic energy is a function of both mass and velocity.