Electrolyte: definition in chemistry
Electrolyte: A substance that conducts electricity when melted or dissolved in water, because it forms ions that are free to move.
Strong electrolytes such as sodium chloride and hydrochloric acid break up completely into ions in water, while weak electrolytes such as acetic acid form only a few ions. Substances that dissolve as whole molecules, such as sugar, are nonelectrolytes and do not conduct. In batteries and electrolysis cells the electrolyte carries charge between the electrodes, and in the body dissolved ions such as Na⁺ and K⁺ carry nerve and muscle signals.
Examples
- Sodium chloride dissolved in water — a strong electrolyte
- Vinegar (acetic acid) — a weak electrolyte
- Sulfuric acid inside a car's lead–acid battery
- Sports drinks replacing sodium and potassium ions lost in sweat
On the periodic table
Compounds formed between metals on the left of the table and nonmetals on the right, such as NaCl and KCl, are typically strong electrolytes.