Which of the following assumptions is not valid for an ideal gas ?
A
molecules of a particular gas are identical
B
molecules moves freely throughout the volume of the container
C
force of attraction between molecules is negligible
D
molecules move at constant speed between collisions
Verified Correct Answer: D.
Physical Principles & Numerical Solution
In an ideal gas, molecules do not move at constant speed between collisions. Their speeds vary due to elastic collisions with other molecules and the walls of the container. The other assumptions—identical molecules, free movement throughout the container, and negligible forces of attraction—are valid for an ideal gas.
Source: Myschool Past Questions Archive (Record #35449)