According to the normality equation, how is normality defined?

Normality is defined as the concentration of a solution in terms of equivalent solute per liter of solution. Specifically, it reflects the reactivity of the solute in relation to acid-base reactions or redox reactions. The equation for normality indicates that it is calculated by multiplying the molarity of the solution by the number of equivalents (H+ ions in acids or OH- ions in bases) that each molecule can produce in reactions.

When considering option C, it accurately states that normality (N) is equal to the molarity multiplied by the number of H+ ions in acids or OH- ions in bases. This captures the essence that normality accounts for the active species that participate in reactions. For example, sulfuric acid (H2SO4) has two equivalents of H+ ions per molecule, so its normality would be twice the molarity.

Other options do not correctly convey the definition of normality. For instance, the first option mistakenly adds molarity and the number of equivalents instead of multiplying them, which does not align with the definition of normality. The second option mentions volume, which is not a factor in calculating normality directly from molarity. The last option inversely relates molarity to the number of