Energy has corresponding intensive (size-independent) properties for pure materials. A corresponding intensive property is specific internal energy, which is energy per mass of substance involved. Specific internal energy is denoted by a lower case u, with dimension of energy per mass (SI unit: joule/kg).
Applicable units are those of quantitykind:SpecificEnergy
http://en.citizendium.org/wiki/Enthalpy
https://cdd.iec.ch/cdd/iec61987/iec61987.nsf/ListsOfUnitsAllVersions/0112-2---62720%23UAD173
Energy has corresponding intensive (size-independent) properties for pure materials. A corresponding intensive property is specific internal energy, which is energy per mass of substance involved. Specific internal energy is denoted by a lower case u, with dimension of energy per mass (SI unit: joule/kg).
$u = U/m$, where $U$ is thermodynamic energy and $m$ is mass.
http://www.iso.org/iso/catalogue_detail?csnumber=31890