JEE Advanced levelOne or more correct optionsDifficulty 3 of 3ig161
A sample of an ideal gas is compressed isothermally from 4.0L to 1.0L. Which statements are correct?
AThe pressure becomes four times the initial pressure
BThe average kinetic energy of the molecules is unchanged
CThe number of molecular collisions with the walls per unit area per unit time increases
DThe rms speed of the molecules increases
Answer: A, B, C
Boyle's law: P∝1/V, so P becomes 4× (A). Kinetic energy and rms speed depend only on T, which is constant (B correct, D wrong). Higher number density raises the collision frequency with the walls, which is why P rises (C).