Sodium metal is soft and reacts vigorously with water, while sodium chloride is familiar as salt. Sodium ions also help cells transmit signals and regulate water balance. The contrast between reactive metal and dissolved ion demonstrates why chemical form matters when describing an element.
FROM ELEMENT TO APPLICATION
AN ELEMENT IN CONTEXT
How can dissolved sodium chloride become several different industrial products?
Sodium chloride compound
FOLLOW THIS RELATIONSHIP
Begin with dissolved ions
Brine contains sodium and chloride ions in water; dissolving the salt separates ions but does not yet make the intended industrial products.
Explore the model (optional)
NaFORM → INTERACTION → CONSEQUENCE
Follow the explanation in either direction. These are authored steps, not a physical clock.
Sodium compounds served everyday purposes long before anyone saw the element itself: salt preserved food, while soda supported glassmaking. In 1807 Humphry Davy used electricity to obtain sodium metal from a sodium compound. Its striking reactivity showed why it had remained hidden in combined forms. The following year, French chemists obtained the metal by a different chemical route, strengthening the identification.
1807
Metal isolated
Davy obtained sodium at the Royal Institution using electricity.
1808
Another route established
Joseph Louis Gay-Lussac and Louis Jacques Thénard produced sodium chemically.
Sodium occurs in salts and numerous , including sodium chloride and cryolite. The metal's readiness to react means that familiar natural sources contain sodium chemically combined with other elements. Extracting the element changes its chemical form; it does not simply separate shiny metal already present inside a salt .
Fresh sodium is a soft, silvery metal whose exposed surface reacts readily. Reaction with water produces a strongly alkaline sodium compound and hydrogen gas. Sodium in stable salts behave very differently from the elemental metal, illustrating why an element's identity alone cannot describe a material's behavior.
Each section links its supporting references. Descriptions and diagrams were authored for this atlas. Source checks completed. Source checks dated 2026-09-06.
CITE THIS PAGE
Family labels and the group-3 layout are teaching conventions. A table position does not establish an unknown bulk property. Electronic configurations refer to neutral atoms; ions and material environments require their own account.
Read each reference property together with its units, conditions and the reference information below.
Not yet recorded: electron affinity, second ionization energy, ground-state term symbol, van der waals radius, thermal conductivity, specific heat capacity, electrical resistivity, crystal structure, lattice parameter a, space group, abundance in seawater, abundance in the universe, annual production, supply-risk listing, hazard classification, biological role, cas registry number, pubchem cid, wikidata item. These families are declared and awaiting an ingestion run against the source each names; they are listed here rather than shown as empty rows.
Physical
Intended reference: CRC Handbook of Chemistry and Physics · CRC Press
Phase at 20 °C
solid
293.15 K, 101.325 kPa
Melting point in K
370.94 K
at standard pressure unless noted
Boiling point in K
1156 K
101.325 kPa
Density in g/cm³
0.968 g/cm³
solids and liquids at 293 K; gases at 273 K and 101.325 kPa
Atomic and electronic
Intended reference: Pauling electronegativity scale · Widely tabulated; original in The Nature of the Chemical Bond
Electronegativity in Pauling
0.93 Pauling
Pauling scale
First ionization energy in kJ/mol
495.8 kJ/mol
gas-phase neutral atom, ground state
Covalent radius in pm
166 pm
single-bond covalent radius
Common oxidation states
+1
states met in ordinary compounds; not exhaustive
Occurrence and identity
Intended reference: CRC Handbook of Chemistry and Physics · CRC Press
Abundance in the crust in mg/kg
23600 mg/kg
upper continental crust, mass fraction
Has stable isotopes
Yesderived
Discovery year in CE
1807 CEderived
WHERE IT SITS AMONG ITS NEIGHBORS
Electronegativity across period 3
Na 0.93 Pauling · Sodium
Electronegativity across period 3. Exact values.
Na
0.93
Mg
1.31
Al
1.61
Si
1.9
P
2.19
S
2.58
Cl
3.16
Electronegativity down group 1
Na 0.93 Pauling · Sodium
Electronegativity down group 1. Exact values.
H
2.2
Li
0.98
Na
0.93
K
0.82
Rb
0.82
Cs
0.79
The trend uses the same reference-property values as the periodic table. Elements with no recorded value are left out of the line rather than drawn at zero.
