Question

When does molarity become equal to normality.

Answer 1

Normality" refers to the activity of a reagent: how many moles of active species are there per liter? For Brønsted acids and bases, normality refers to how many moles of H+ or OH-there are per liter.Thus, for hydrochloric acid (HCl) and sodium hydroxide (NaOH) the normality is equal to the molarity. But for dibasic substances like sulfuric acid (H2SO4) or barium hydroxide Ba(OH)2, the normality is twice the molarity. For a tri basic substance, normality would be three times the molarity and so forth.