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Material World
Element · Na

Sodium

A metal so reactive it is stored under oil, and half of ordinary table salt.

Sodium metal reacts violently with water and tarnishes within seconds in air, so it is never encountered as a metal outside a laboratory or a chemical plant. It is encountered constantly as a compound — sodium chloride, sodium carbonate, sodium hydroxide — and those compounds sit at the base of the chemical industry.

The contrast is instructive: an element's everyday familiarity has nothing to do with the properties of the element itself.

Uses

Sodium metal itself has narrow uses — as a heat-transfer fluid in some reactor designs, and as a reducing agent in chemical synthesis — because it reacts violently with water and must be handled under oil.

Its compounds are another matter entirely. Sodium chloride is the feedstock for chlorine and sodium hydroxide, and sodium carbonate is essential to glassmaking, where it lowers silica's melting point to something a furnace can reach. Nearly all sodium's industrial importance is as a counter-ion.

Medium confidence Weak evidence

How we know: checked recently · only one source, so there is nothing to cross-check it against · stated directly by the source.

How this connects

Where a connection has been confirmed by an outside reference, that reference is named beside it.

is used as

  • Catalysis — application · sodium compounds are among the commonest industrial bases

is extracted from

  • Halite — mineral · the same electrolysis; sodium metal is made from molten salt rather than brine Wikidata

is found in

  • Sodium hydroxide — compound
  • Albite — mineral Wikidata
  • Seawater — material · with chloride, and the pair make up something like eighty-five per cent of what is dissolved
  • Salt — compound · forty per cent by mass, and the part the body needs
  • Borax — mineral Wikidata
  • Halite — mineral Wikidata
  • Plagioclase — mineral · substitutes within a solid solution — an individual specimen may hold little of it
  • Pollucite — mineral · substitutes within a solid solution — an individual specimen may hold little of it

is produced by

is an alternative to

  • Lithium — element · in batteries: sodium-ion cells store less energy for their mass and are made from an element nobody has to secure, which suits stationary storage and does not suit a phone

Sources

  • Material World
    Our own writing
  • Wikidata
    Wikimedia Foundation · Creative Commons CC0 1.0 Universal (public domain dedication)
  • PubChem
    US National Library of Medicine · Mixed — aggregated third-party content, rights retained by depositors
  • NIST — National Institute of Standards and Technology
    United States Department of Commerce · US Government work — public information, credit requested

Questions this page answers

Where it comes from, and what it becomes

Follow Sodium back to what it starts as, and forward into what it becomes. Each step is a documented one — a real route material takes, not a chain of inference.

Upstream — what it comes from

  • Sodium → is produced by (from molten sodium chloride, with chlorine released at the anode) → Molten salt electrolysis → takes as input (after concentration, as one of the two routes to lithium chloride) → Lepidolite
  • Sodium → is extracted from (the same electrolysis; sodium metal is made from molten salt rather than brine) → Halite

Downstream — what it becomes

  • Sodium → is used as (sodium compounds are among the commonest industrial bases) → Catalysis