Question

define limiting agent. identify the limiting reagent if any in the following reaction mixture .
(a) 100 atoms of A + 5 mol B .
(b) 2.5 mol A + 5 mol B .​

Answer 1

Answer:

Explanation:

while solving the problems relating to chemical equation,the reactant react according to the balanced chemical equation.Quite often, one of the reactant is present in lesser amount while the other may be present in higher amount.The reactant which is present in lesser amount is known as limiting reactant or reagent.

if reaction is A + B2 → AB2

(a) According to the given reaction, 1 atom of A reacts with 1 molecule of B. Thus, 5 molecules of B will react with 5 atoms of A, thereby leaving 195 atoms of A unused. Hence, B is the limiting reagent.Here atom B is in lesser amount.

(b) According to the reaction, 1 mol of atom A combines with 1 mol of molecule B. Thus, 2.5 mol of A will combine with only 2.5 mol of B and the remaining 2.5 mol of B will be left as such. Hence, A is the limiting reagent.