Answer: (a) Neon, Nitrogen; (b) Neon, Nitrogen; (c) Neon is lower than Nitrogen; (d) It doesn't affect;
Explanation: The kinetic-molecular theory studies the behavior of particles under pre-determinated situation. In cases of gases, the particles moving around colliding with each other and the walls of the container, without loss of energy. In the case in question, all the parameters are the same (same temperature, volume and pressure), except for the gases, which has different molar masses. In this sense, Neon has lower average speed due to its molar mass being higher, which means, its particles moves slower for being heavier. Related to pressure, as velocity is lower, it collides less with the walls of the tank, and so pressure is lower. For density, it doesn't affect the behavior of the system nor the kinetic energy.
