Thanks everyone for your input.. I understand all the points presented, but I still feel inclined to assume the gas molecules lose velocity in a direction other than just normal to the surface of the container.. Doesn't viscosity have some effect on the tangential component of the gas molecules'...
My question is about the energy exchange between gas particles and the walls of their container...
If you consider a collection of gas molecules enclosed in a container, if the whole system is cooled (ie. like a balloon dipped in liquid nitrogen) as the gas particles collide with the inner...