Below a certain threshold pressure, the air molecules (0.3 nm diameter) within a research vacuum chamber are in the "collision-free regime", meaning that a particular air molecule is as likely to cross the container and collide first with the opposite wall, as it is to collide with another air molecule. Estimate the threshold pressure for a vacuum chamber of side 1,0 m at 20 °C.

Below a certain threshold pressure, the air molecules (0.3 nm diameter) within a research vacuum chamber are in the "collision-free regime", meaning that a particular air molecule is as likely to cross the container and collide first with the opposite wall, as it is to collide with another air molecule. Estimate the threshold pressure for a vacuum chamber of side 1,0 m at 20 °C.