ENTHALPHY

ENTHALPY

• In a thermodynamic system, enthalpy is a way to measure energy.
• The total amount of heat in a system is equal to its enthalpy, which is equal to its internal energy plus the product of its volume and pressure.

        H = E + PV

• H (enthalpy): It encompasses the total energy content of a system, considering both its internal energy and the energy associated with its volume and pressure.
• e (internal energy): This represents the inherent energy of the system at the molecular level, including the kinetic and potential energy of its particles.
• P (pressure) is the force that the system applies to its surroundings or container.
• Volume (v): This represents the area that the system occupies.
• The pv term (pressure-volume work) accounts for the energy exchanged between the system and its surroundings due to changes in volume against pressure.
• When the system expands against a constant pressure, work is done, and the pv term contributes positively to the enthalpy.
• Conversely, when the system is compressed, work is done on it, and the pv term subtracts from the enthalpy.

Knowing this equation, you can:

• Predict the change in enthalpy (ΔH) for a process by considering changes in internal energy and pressure-volume work.
• Analyze the heat flow (q) during a process by relating it to the change in enthalpy using the first law of thermodynamics: q = ΔH + w (w is the total amount of work the machine did).
• Solve thermodynamic problems involving enthalpy, pressure, volume, and internal energy.

IMAGE SOURCE (THUMBNAIL)