Enthalpy — Chemistry Definition | AllChemicals | AllChemicals

What is Enthalpy?

Enthalpy (H) is a thermodynamic quantity equal to the internal energy of a system plus the product of its pressure and volume (H = U + PV). The change in enthalpy (ΔH) at constant pressure equals the heat absorbed or released in a chemical reaction. Exothermic reactions have negative ΔH; endothermic reactions have positive ΔH. Standard enthalpy values are measured at 298 K and 1 atm.

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What is Enthalpy?

Enthalpy (H) is a thermodynamic quantity equal to the internal energy of a system plus the product of its pressure and volume (H = U + PV). The change in enthalpy (ΔH) at constant pressure equals the heat absorbed or released in a chemical reaction. Exothermic reactions have negative ΔH; endothermic reactions have positive ΔH. Standard enthalpy values are measured at 298 K and 1 atm.

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