Mercury (Hg)

Mercury properties

Atomic number

80

Atomic mass

200.59 u

Category

Transition metal

Group

12

Period

6

Block

d-block

State at room temp.

Liquid

Electronegativity

2

Melting point

234.32 K (-38.8 °C)

Boiling point

629.88 K (356.7 °C)

Density

13.534 g/cm³

Valence electrons

2

Common charges

+1, +2

Oxidation states

+2, +1

Atomic radius

209 pm

Ionization energy

10.438 eV

Electron affinity

—

Radioactive

No, has stable isotopes

Discovered

Ancient

Mercury electron configuration

The electron configuration of Mercury (Hg) is [Xe] 4f14 5d10 6s2. Its 80 electrons are arranged in shells as 2, 8, 18, 32, 18, 2.

Protons, neutrons and electrons in Mercury

A neutral Mercury atom has 80 protons and 80 electrons. Most Mercury atoms have about 121 neutrons: the atomic mass rounded to 201, minus the atomic number 80.

Neutrons are approximate: atoms of the same element can have different numbers of neutrons (isotopes). Atomic number and mass

How many valence electrons does Mercury have?

2

Mercury has 2 valence electrons, counting the electrons in its outermost s subshell. Like most transition metals, it can also use d electrons in bonding.

See every element: Periodic table with valence electrons

Mercury orbital diagram

Each box is an orbital that holds up to two electrons with opposite spins (↑↓). The inner shells are the same as the noble gas in brackets. How to write electron configurations

Molar mass of Mercury

200.59 g/mol

One mole of Mercury atoms (6.022 × 10²³ atoms) has a mass of 200.59 grams. Use this value to convert between grams and moles.

Compounds containing Mercury

Mercury facts

• Mercury is the only metal that is liquid at room temperature.
• Mercury (Hg) has atomic number 80 and is a liquid at room temperature. It has been known since ancient times.

Position in the periodic table

Mercury is element 80, in period 6 and group 12 of the periodic table, in the d-block.

All transition metals

Uses of Mercury

Mercury's uses are shrinking because it is highly toxic. Mercury vapor still makes some fluorescent lamps glow, and mercury has long been used in dental amalgam fillings, thermometers, barometers, and electrical switches, though many of these uses are being phased out under the 2013 Minamata Convention. Some chemical plants still use mercury to produce chlorine and sodium hydroxide.

Who discovered Mercury?

Mercury has been known since ancient times and was used by ancient Chinese, Indian, Egyptian, Greek, and Roman cultures, as well as by alchemists. Its symbol, Hg, comes from its Latin name hydrargyrum, from the Greek for 'water-silver'.

Where does the name come from?

Mercury is named after the planet Mercury, which alchemists linked with this fast-flowing liquid metal; the planet honors the swift messenger god of Roman mythology. The symbol Hg comes from the Latin hydrargyrum, from the Greek for 'water silver'.

Discovery timeline