Question

Define enthalpy. At cosntant pressure show that
ΔH = ΔU + P · ΔV

Answer 1

enthalpy is the total heat content of the system at constant pressure.

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Answer 2

At the time of process of the taken out on at constant pressure , the heat absorbed or get released is equal to the change of the enthalpy .

The enthalpy is represented as the H which is total sume of the internal energy as well as the pressure.

Hence H= U+ PV and you have to multiple with the Del and get Δ H= Δ U+ P Δ V.