How does enthalpy change with pressure?

1 Answer

Enthalpy does not change with pressure if everything else remains constant.

#H = U + PV#

For an ideal gas,

#ΔH = ΔU + Δ(PV) = ΔU + Δ(nRT) = ΔU + nRΔT#

U depends only on the temperature.

If temperature remains constant, #ΔU# = 0 and #ΔT#= 0.

#ΔH# = 0 + 0 = 0.

Enthalpy does not change with pressure.