Molar Mass of Sulfuric Acid

At 98.072 g/mol and two available protons, sulfuric acid has an equivalent weight of 49.04 g/eq, so its normality is always twice its molarity. Concentrated reagent acid is 98 % w/w with a density of 1.84 g/mL, which works out to 18.4 mol/L — one of the few concentrations worth memorising, and the reason a "1 M" dilution is prepared by adding 54 mL of concentrate to water and never the reverse.

Sulfuric acid is produced in greater tonnage than any other industrial chemical, and its consumption has been used since the nineteenth century as a proxy for a country's industrial output. In cooling towers and boilers it is the standard reagent for alkalinity reduction: each mole neutralises two moles of bicarbonate, so 49.04 g of acid destroys one equivalent, or 50.04 g as CaCO₃, of alkalinity — a near one-to-one mass ratio that makes field dosing arithmetic unusually forgiving.