080Transition metal · Group 12 · Period 6

Mercury

Mercury (Hg) is element 80, a transition metal in the d-block — group 12, period 6. It is a liquid at room temperature with 6 electron shells (2, 8, 18, 32, 18, 2) and an atomic mass of 200.5923 u.

Atomic mass: 200.6 u
Phase · STP: liquid
Melting: 234 K · -39 °C
Boiling: 630 K · 357 °C
Electronegativity: 2
Density: 13.534 g/cm³

Photograph — Hi-Res Images of Chemical Elements, CC BY 3.0 <https://creativecommons.org/licenses/by/3.0>, via Wikimedia Commons, source: https://images-of-elements.com/mercury.php

Identity

Atomic number: 80
Standard atomic weight: 200.6 u
Category: Transition metal
Group: 12
Period: 6
Block: d-block
Oxidation states: +2, +1

Physical properties

Melting point: 234 K · -39 °C
Boiling point: 630 K · 357 °C
Density: 13.534 g/cm³
Molar heat capacity: 27.983 J/(mol·K)
Atomic radius: 209 pm
Electron affinity: -48 kJ/mol

Atomic structure

80protons

121neutrons

80electrons

2valence e⁻

Noble-gas notation: [Xe] 4f14 5d10 6s2
Full configuration: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10
Electrons per shell: 2, 8, 18, 32, 18, 2

Periodic trends

Where Mercury ranks across all 118 elements.

Electronegativity2

Ionization energy1007.1 kJ/mol

Electron affinity-48 kJ/mol

Density13.534 g/cm³

Atomic radius209 pm

Ionization energies

Energy to remove each successive electron (kJ/mol).

1.0k

1.8k

3.3k

Successive ionization energies (kJ/mol, log scale).

Discovery

Discovered: Ancient
Discovered by: unknown, before 2000 BCE
Named by: —
Appearance: silvery