F Standard State of Elements

All elements are a solid at 25 °C and 1 bar (0.1 MPa) with the following exceptions:

Liquids Monatomic gases Diatomic gases

Bromine, Br2(l)

Helium, He(g)

Hydrogen, H2(g)

Mercury, Hg(l)

Neon, Ne(g)

Nitrogen, N2(g)


Argon, Ar(g)

Oxygen, O2(g)


Krypton, Kr(g)

Fluorine, F2(g)


Xenon, Xe(g)

Chlorine, Cl2(g)


Radon, Rn(g)