Which of the Following Molecules/atoms Will Exert a Greater Force

Multiple Choice

Which of the following molecules/atoms will exert a greater force when it strikes the wall of the container under ideal conditions?

A) Cs atoms at 240 m/s
B) Naphthalene molecules (C₁₀H₈) at 250 m/s
C) Radon atoms at 200 m/s
D) He atoms at 800 m/s
E) Ar atoms at 300 m/s