Cambridge Science – States of Matter Practice Test

Table salt is sodium chloride, NaCl, the compound made of sodium ions and chloride ions that we use to season and preserve food. In water it dissociates into Na+ and Cl−, which gives the familiar salty taste. The other substances are different salts with different ions: potassium chloride (KCl) is a different chloride salt sometimes used as a salt substitute; sodium bicarbonate (NaHCO3) is baking soda; sodium sulfate (Na2SO4) is an industrial salt. Because only sodium chloride is the edible table salt, it is the correct identification.