kinetic theory equation

Change in momentum of molecule colliding with walls of container is Δp =

Momentum before = mu

Momentum after = -mu

change in momentum = 2mu

Time taken between successive collisions of molecule with wall is t =

Distance/speed = 2L/u

Frequency of collisions with wall is f =

u/2L

Average force on (from) 1 molecule is F (1 molecule) =

2mu x u/2L = mu²/L

Average force on (from) N molecules is F =

Pressure on wall is p = 

For one molecule, with velocity components u, v and w, square speed is c^2 ₌

u^2 ₊ v²+ w²

So finally

pV = 1/3 Nm(average c)²