Question

In a reaction
`A+B_(2) rarr AB_(2)`
Identify the limiting reagent, if any, in the following reaction mixtures.
a. `300 "atoms"` of `A+ 200` molecules of `B`
b. `2 mol A+3 mol B`
c. `100 "atoms"` of `A+100` molecules of `B`
d. `5 mol A+2.5 mol B`
e. `2.5 mol A + 5 mol B`

Answer 1

According to the given reaction, `1` atom of A reacts with `1` molecule of `B`.
`:. 200` molecules of `B` will react with `200` atoms of `A` and `100` atoms of `A` will be left unreacted. Hence, `B` is the limiting reagent while `A` is the excess reagent.
b. According to the given reaction, `1` mole of `A` mol of `A` reacts with `1 mol` of B
`:. 2 mol` of `A` will react with `2 mol` of `B`. Hence, `A` is the limting reactant.
c. No limiting reagent.
d. `2.5 mol` of `B` will react with `2.5 mol` of `A`. Hence, `B` is the limiting reagent.
e. `2.5 mol` of `A` will react with `2.5 mol` of `B` Hence, `A` is the limiting reagent.