Question

What Is The Significance Of The Thermodynamic Enthalpy?

Answer 1

Enthalpy:

• Enthalpy is a state function.
• The enthalpy, H, is equal to the sum of the internal energy, U, and the product of the pressure, P, and volume, V, of the system.
• It can be expressed as: $\mathrm{H}=\mathrm{U}+\mathrm{pV}$.
• H is a state function because it depends on U, p, and V, all of which are state functions.
• Therefore, $∆\mathrm{H}$ is independent of the path.
• Thus, it can be expressed as: $∆\mathrm{H}=∆\mathrm{U}+\mathrm{p}∆\mathrm{V}$.

Significance of Enthalpy:

• Calculating the change in enthalpy tells whether a reaction is endothermic (absorbed heat, positive change in enthalpy) or exothermic (released heat, a negative change in enthalpy.)
• It is beneficial in calculating the heat of the reaction of a chemical process.