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Hg

Mercury

Mercury is a chemical element with the symbol Hg and atomic number 80. It has a standard atomic weight of 200.59, sits in period 6 and group 12, and is classified as a transition metal.

Properties

SymbolHg
Atomic number80
Standard atomic weight200.59
CategoryTransition metal
Group12
Period6
Electron configuration[Xe] 4f14 5d10 6s2
Outer-shell electrons2

The figure of 200.59 is a standard atomic weight.

Compounds containing mercury

1 of the compounds in this reference contain Hg, listed by the fraction of their mass it makes up.

CompoundFormulaAtoms% by mass
mercury chlorideClHg185.0%

Calculate with mercury

Group 12

Atomic weights are the IUPAC 2021 standard values, abridged to the conventional five significant figures. Group, period, category and electron configuration are derived from the atomic number rather than stored, so they cannot drift out of step with it.