internal energy of a system plus the product of pressure and volume. Its change in a system is equal to the heat brought to the system at constant pressure.
Green Book, 2nd ed., p. 48 [Terms
PAC, 1990, 62, 2167. (Glossary of atmospheric chemistry terms (Recommendations 1990)
) on page 2187 [Terms
PAC, 1996, 68, 957. (Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)
) on page 972 [Terms