# Exercise 1. Calculate the work associated with gas expansion.

Calculate the work associated with the expansion of a gas from 46 L to 64 L at a constant external presure of 15 atm.

Solution:

The work required to expand a gas against a exterior presure is: $$w=-P\Delta V$$ In this case: $\Delta V=64-46=18\; L$ Hence: $$w=-15\;atm\cdot18\;L=-270\;atmL$$ Works is negative, since the gas expanding.