Element 80 · Transition metal
Mercury (Hg) — Element 80
Planet Mercury
Mercury (Hg) is a transition metal in Period 6, Group 12 of the periodic table with atomic number 80, standard atomic weight 200.59 u, and ground-state electron configuration [Xe] 4f¹⁴ 5d¹⁰ 6s². At standard temperature and pressure it is classified as a liquid with 12 valence electrons and common oxidation states +1, +2.
Thermometers, fluorescent lamps
What are the atomic properties and physical constants of Mercury?
Reference constants compiled from IUPAC standard atomic weights, the NIST Atomic Spectra Database, and the CRC Handbook.
- Atomic number (Z)
- 80
- Standard atomic mass
- 200.59 u
- Chemical family
- Transition metal
- Ground-state configuration
- [Xe] 4f¹⁴ 5d¹⁰ 6s²
- Electrons per shell
- 2, 8, 18, 32, 18, 2
- Valence electrons
- 12
- Common ion charges / oxidation states
- +1, +2
- Phase at STP
- Liquid
- Pauling electronegativity
- 2.00 Pauling
- First ionization energy
- 1,007 kJ/mol
- Atomic radius
- 171 pm
- Melting point
- -39 °C
- Boiling point
- 357 °C
- Discovery year
- Ancient
- Table coordinate
- Period 6, Group 12
- Radioactivity
- Has stable isotope(s)
How are electrons arranged across Mercury’s shells?
A neutral Mercury atom contains 80 electrons distributed across 6 occupied principal energy shells ([Xe] 4f¹⁴ 5d¹⁰ 6s²). The table below compares Mercury’s shell occupancy against each shell’s theoretical 2n² capacity.
| Principal Shell (n) | Spectroscopic Letter | Electrons in Hg | Max Shell Capacity (2n²) |
|---|---|---|---|
| n = 1 | K | 2 e⁻ | 2 e⁻ |
| n = 2 | L | 8 e⁻ | 8 e⁻ |
| n = 3 | M | 18 e⁻ | 18 e⁻ |
| n = 4 | N | 32 e⁻ | 32 e⁻ |
| n = 5 | O | 18 e⁻ | 50 e⁻ |
| n = 6 | P | 2 e⁻ | 72 e⁻ |
Frequently Asked Questions about Mercury (Hg)
What is the atomic mass and atomic number of Mercury (Hg)?
Mercury (Hg) has atomic number Z = 80 (80 protons in its nucleus) and an IUPAC standard atomic weight of 200.59 u. It sits in Period 6, Group 12 and is classified as a transition metal.
What is the ground-state electron configuration of Mercury?
The neutral ground-state electron configuration of Mercury (Z = 80) is [Xe] 4f¹⁴ 5d¹⁰ 6s². Across its 6 occupied principal shells (n = 1 to n = 6), the electrons per shell are 2, 8, 18, 32, 18, 2, with 12 valence electrons participating in bonding.
What are the common ion charges and electronegativity of Mercury?
Mercury commonly forms +1, +2 oxidation states or ion charges in compounds. Its Pauling electronegativity is 2.00 and its first ionization energy is 1,007 kJ/mol.
When was Mercury discovered and what is it used for?
Mercury was discovered in Ancient (Planet Mercury). Thermometers, fluorescent lamps
How does Mercury compare to neighboring elements?
Other transition metal elements: