The solvent is a compound of which there is more. And the solute is a compound of which there is less. So let's go back to our examples in brass, brass is composed of 55% copper and 45% zinc. So there's more copper, which means copper is a solvent and zinc is a solute. In this example, there's more water than sodium, chloride or salt. So the solvent is water and the solute is the salt.