# What is isothermal expansion?

Dec 17, 2016

The plot of a pressure versus volume diagram held at a constant temperature that shows the volume increasing.

#### Explanation:

An isothermal process refers to a change of a system, in which the temperature remains constant ($\Delta T = 0$).

The graph above shows a pressure vs. volume graph (called an isotherm). During an expansion, the final volume becomes larger than the initial volume, which is indicated by the purple arrow going in the forward ($\rightarrow$)direction.