Which term describes the point at which the reactants have reacted in stoichiometric proportions?

• A. End point
• B. Stoichiometric point
• C. Equivalence point
• D. Theoretical point

Answer: (B)

The key idea is reaching a state where the amounts of reactants match the ratios given by the balanced equation. When the reaction proceeds so that the reactants are consumed in those exact proportions, you’ve hit the stoichiometric point. At this moment, if the reaction goes to completion, the limiting reactant has been fully used and the other reactants are present in the precise amounts dictated by the equation. In titration contexts this is the point you’re aiming for—often called the equivalence point—where the quantities are chemically equivalent. The term emphasized here, stoichiometric point, directly captures the idea of exact proportional consumption. An endpoint is just what you observe (like a colour change) and may not align exactly with this balance, and a term like theoretical point isn’t a standard descriptor.