Mercury (Hg)

Shiny, silvery liquid

Mercury is the only metal that's liquid at room temperature, and it's extremely toxic, and with [Xe] 4f¹⁴ 5d¹⁰ 6s², relativistic contraction of the 6s shell makes mercury's metallic bonding so weak it's liquid at 234 K. It amalgamates with gold and was used in hat-making (hence 'mad as a hatter').

Key metrics

Density13.53g/cm³

Melting point234K

Boiling point630K

Electronegativity2Pauling

Discovery

-2000discovered

Discovered by: Ancient civilizations
Reactivity profile: Toxic liquid metal
Reactivity: Medium
Bonding: Metallic

Electron configuration

\textcolor{#6b7280}{[Xe]}\; \textcolor{#a855f7}{4_{f}^{14}}\; \textcolor{#22c55e}{5_{d}^{10}}\; \textcolor{#ef4444}{6_{s}^{2}}

[Xe] 4f14 5d10 6s2

Wave function

\Psi_{\text{Hg}} \approx \frac{1}{\sqrt{80!}} \det \left| \chi_1(\mathbf{r}_1) \dots \chi_{80}(\mathbf{r}_{80}) \right|

Probability density $|\Psi|^2$ across the Hg valence shell.

Crystal structure

Rhombohedral

Lattice constantsa 1.00 · b 1.00 · c 1.00

Cell anglesα = β = γ = 61.5°

Coordination number—

Atoms per cell—

Atomic packing factor0.53

Physical properties

Atomic radius: 151 pm
Ionization energy: 1007 kJ/mol
Electron affinity: 0 kJ/mol
Crystal structure: Rhombohedral

Oxidation states

+1+2

Acid/base

Neutral

Strongly acidicStrongly basic

State at 25 °CLiquid

234 K630 K298 K

Emission spectrum

4 transitions

380450500550600650700780

VioletBlueGreenYellowRed

435.8nmHg I (blue)Violet90%

546.1nmHg I (green)Green100%

577.0nmHg I (yellow)Yellow70%

579.1nmHg I (yellow)Yellow70%

Dominant line 546.1 nmRange 436–579 nmTransitions 4