Which of the following is not true about limiting and excess reagents? a. the amount of product obtained is determined by the limiting reagent. b. a balanced equation is necessary to determine which reactant is limiting reagent. c. some of the excess reagent is left over after the reaction is complete. d. the reactant that was the smallest given mass is the limiting reagent.

Answer : The incorrect option is, (d) The reactant that was the smallest given mass is the limiting reagent.

Explanation :

Limiting reagent : It is the reagent that is completely consumed in the chemical reaction when the chemical reaction is complete. No amount is left after the reaction is complete. The amount of product obtained is determined by the limiting reagent. A balanced equation is necessary to determine which reactant is limiting reagent.

Excess reagent : It is the reagent that are not completely consumed in the chemical reaction. That means the reagent is in excess amount. Some amount of the excess reagent is left over after the reaction is complete.

From this we conclude that the options, A, B and C are correct. While the option D is incorrect.

Option D is incorrect because it is not necessary the reactant that was the smallest given mass is the limiting reagent but it is judge by the number of moles present in the reaction.

Hence, the incorrect option is, (d)

it is the most commonly accepted one