Saltwater is a good conductor of electricity because it is an electrolyte solution. Substances such as salts, acids and hydroxides that also are electrolytes can conduct electric current. Saltwater is a mixture that consists of water and sodium chloride. When sodium chloride dissolves in water, the water separates the sodium and chlorine ions.
Saltwater separates into a positively charged sodium ion and a negatively charged chloride ion. Ions are atoms that have either a positive or negative electric charge, depending on whether they gain or lose electrons. A metal like sodium forms positively charged ions. A chloride ion is a non-metal, and it forms a negatively charged ion.
Although saltwater is a conductor of electricity, pure water is not. Making a saltwater circuit is an experiment that demonstrates saltwater’s ability to conduct an electrical charge. To perform this experiment, one needs items that include a 9-volt battery, light bulb, insulated copper wires, beakers, salt and water.
Sodium chloride has the chemical formula NaCl. It also is an ionic compound. If a compound dissolves in an aqueous solution and can conduct electricity, it is called an electrolyte. Conversely, if a compound does not conduct electricity when it dissolves and becomes a solution, it is a nonelectrolyte. Compounds that consist of only non-metals are examples of nonelectrolytes.