*stoichiometrical*

{ } a. Of or pertaining to stoichiometry; employed in, or obtained by, stoichiometry. [ 1913 Webster ]

2. (Chem.) of, pertaining to, using, or consuming, reagents in the exact proportions required for a given reaction; as, a stoichiometric reaction, i. e., a reaction which goes to completion, rather than stopping partway at an equilibrium point. [ PJC ]