What term describes the number of equivalent weights of solute per liter of solution?

The term that describes the number of equivalent weights of solute per liter of solution is known as normality. Normality is a measure particularly used in chemistry to express the concentration of a solution in terms of equivalents per liter. An equivalent weight takes into account the reactive capacity of a solute, which varies depending on the type of reaction it participates in.

This concept is especially important in acid-base reactions, redox reactions, and precipitation reactions where the exact amount of solute that reacts or participates in a given process is critical. For instance, one equivalent of sulfuric acid (H₂SO₄) can provide two moles of hydrogen ions (H⁺) in solution, which can significantly affect calculations related to reactants and products in a chemical reaction.

Molarity, while also a concentration measure, expresses the number of moles of solute per liter of solution rather than equivalents. Therefore, normality is specifically designed to convey information about the reactivity of the solute in relation to a given reaction, making it distinct from other concentration measures such as molarity.