Salt Questions · Science, chemistry & environment
How does salt water conduct electricity?
Short answer
When salt dissolves, it splits into positively charged sodium ions and negatively charged chloride ions. These ions can move freely through the water, so when a voltage is applied, they carry electric current. Pure water conducts very poorly, and solid salt doesn't conduct at all, because its ions are locked in place.
How salt water carries current
- 1NaCl dissolves into Na⁺ and Cl⁻ ions
- 2Voltage applied across two electrodes
- 3Na⁺ moves to −, Cl⁻ moves to +
- 4Moving ions = electric current
Ions carry the current
In a metal wire, electrons carry current. In salt water, the ions themselves move: positive sodium ions drift toward the negative electrode and negative chloride ions toward the positive one.
Solid, molten and dissolved
- Solid salt: ions are fixed in the crystal; no current.
- Molten salt (above 801 °C): ions move freely; it conducts.
- Salt water: ions move freely; it conducts, and more salt means more conduction up to a point.
Why it matters
This is why salt water and electrical devices are a dangerous mix, why seawater speeds corrosion, and how water-quality crews estimate salinity: by measuring conductivity. Liquids that conduct this way are called electrolytes.
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Cite this page
For school projects and reports. Teachers often prefer the original sources too: see the list below.
The Salt Almanac. (2026, November 8). How does salt water conduct electricity. https://saltalmanac.com/answers/how-does-salt-water-conduct-electricity
“How does salt water conduct electricity.” The Salt Almanac, 8 Nov. 2026, saltalmanac.com/answers/how-does-salt-water-conduct-electricity. Accessed [today's date].
“How does salt water conduct electricity.” The Salt Almanac. Last modified November 8, 2026. https://saltalmanac.com/answers/how-does-salt-water-conduct-electricity.
Original sources
- Wikipedia. Electrolyte. https://en.wikipedia.org/wiki/Electrolyte
- Wikipedia. Sodium chloride. https://en.wikipedia.org/wiki/Sodium_chloride