Work Done by Gas in Isobaric Process

Scientists define work W to be the product of a force acting through a distance. For a gas, work is the product of the pressure and the volume during a change of volume. Gases can do work through expansion or compression against constant external pressure. This model shows the expansion of gas against the weight of an object's mass on a piston. The initial temperature and final temperature are constant, therefore the change in energy is zero. Thus, the heat absorbed by the gas equals the work done by the ideal gas on its surroundings.