Heat And Thermodynamics

A cubical box of side \(1 \mathrm{~m}\) contains Boron gas at a pressure of \(100 \mathrm{~Nm}^{-2}\). During an observation time of 1 second, an atom travelling with the rms speed parallel to one of the edges of the cube, was found to make 500 hits with a particular wall, without any collision with other atoms. The total mass of gas in the box in gram is