Which liquid best dissolves salt?

Why Water Is the Ultimate Salt Dissolver

If you have ever tried stirring table salt into a glass of water versus a glass of rubbing alcohol, you probably noticed a dramatic difference. Salt vanishes almost instantly in water, while alcohol struggles to break down the crystals. The secret behind this everyday phenomenon comes down to basic molecular chemistry and the concept of polarity.

Table salt, or sodium chloride, is held together by strong ionic bonds between positively charged sodium ions and negatively charged chloride ions. To dissolve these tightly bound crystals, a liquid needs to actively pull those ions apart. This is where polar solvents excel. A polar molecule features an uneven distribution of electrical charge, giving it distinct positive and negative ends.

Water is a remarkably strong polar solvent. Its oxygen atom carries a slight negative charge, while its hydrogen atoms carry a slight positive charge. When salt enters water, these tiny charges act like magnets. The negative ends of water molecules surround the positive sodium ions, while the positive ends surround the negative chloride ions, pulling them away from the crystal lattice.

In contrast, liquids like rubbing alcohol are far less polar. Although alcohol molecules have a polar region, they also contain nonpolar components that do not interact well with charged particles. Because salt ions attract water molecules much more strongly than alcohol molecules, water remains the far superior solvent for dissolving salt.