Isobaric process

Definition

An isobaric process is a thermodynamic process in which the pressure remains constant. Heat added or removed from the system does work on or by the system while changing its internal energy.

5 Must Know Facts For Your Next Test

1. In an isobaric process, the pressure does not change, but volume and temperature can change.
2. The work done by or on the gas in an isobaric process can be calculated using $W = P \Delta V$ where $P$ is pressure and $\Delta V$ is the change in volume.
3. The first law of thermodynamics for an isobaric process can be expressed as $\Delta U = Q - W$, where $\Delta U$ is the change in internal energy, $Q$ is heat added, and $W$ is work done.
4. For an ideal gas undergoing an isobaric process, Charles's Law applies: $V \propto T$ (at constant pressure).
5. In an isobaric expansion, work done by the gas results in a decrease in internal energy if no heat is added.

Review Questions

• What remains constant during an isobaric process?
• How do you calculate the work done by a gas during an isobaric expansion?
• Which law describes the relationship between volume and temperature for an ideal gas undergoing an isobaric process?

Related terms

Isochoric Process: A thermodynamic process in which volume remains constant; no work is done by or on the system.

Isothermal Process: A thermodynamic process at constant temperature; internal energy remains unchanged.

Adiabatic Process: A thermodynamic process with no heat exchange between the system and surroundings; all changes are due to work done on or by the system.