In a certain particle accelerator, protons travel around a circular path of diameter 20.5 m in an evacuated chamber, whose residual gas is at 297K and 1.00×10-6 torr pressure. Calculate the number of gas molecules per cubic centimeter at this pressure. (cm-3).
What is the mean free path of the gas molecules if the molecular diameter is 2.00×10-8 cm? (m)