pv = constant to find the work done
The expression "pv = constant" is known as Boyle's Law, which describes the relationship between the pressure (p) and the volume (v) of an ideal gas at a constant temperature. However, it does not represent a direct equation to find the work done.
To calculate the work done by a gas, you need additional information such as the initial and final volumes, pressures, and the process through which the gas undergoes a change (e.g., isothermal, adiabatic, etc.). The general formula to calculate work done by a gas is:
Work = - P ∆V
where P represents the constant pressure and ∆V is the change in volume (final volume - initial volume).
To find the work done using this formula, you must know the specific values of the pressure and volume at different states.