I have a gas container which contains gas at high pressure. The gas container is fitted with a capillary tube which opens into the atmosphere. Now we have a stopcock fitted to the capillary tube. We opens the stop cock slightly and allows the gas to leak outside. The process will go on till the pressure is equalized on the two sides. Is the gas doing any work?? My second question features the same arrangement. Only now the container is vacuum. now the stop cock is opened slightly and the gas is allowed to enter. Now is this process involve any work???