(i) What is the most likely speed for a molecule of mass 'm' at room temperature T in a 3D space? (ii) What is the most likely speed for a molecule of mass 'm' at room temperature T in a 2D space? (iii) What are the physical origins of the differences between the most likely speed in 3D and in 2D? (iv) Why two identical ideal gas molecules in a room kept at constant temperature may move at different speeds?

(i) What is the most likely speed for a molecule of mass 'm' at room temperature T in a 3D space? (ii) What is the most likely speed for a molecule of mass 'm' at room temperature T in a 2D space? (iii) What are the physical origins of the differences between the most likely speed in 3D and in 2D? (iv) Why two identical ideal gas molecules in a room kept at constant temperature may move at different speeds?