ABSTRACT
When a particular molarity of the acid is called for, it is necessary to know the molarity of the concentrated reagent in order to use the dilution formula. It is thus very common for an analyst to need to prepare solutions of a particular molarity, both by dilution and by weighing a pure chemical. That means that in all calculations performed in which the mole and the molecular weight are used (including solution preparation), the equivalent and equivalent weight may also be used. If one mole of one substance reacts with one mole of another substance, it may be more convenient to work in terms of moles and molarity rather than equivalents and normality. However, if only the molarity of the solution to be diluted is known, it is first necessary to convert to normality. The number of equivalents per mole is, of course, the number by which the molecular weight is divided to obtain the equivalent weight.
