Question

What is the limiting reactant in a reaction where 10.0 mol of iron is treated with 12.0 mol of bromine? The product that forms is FeBr3. First, write and balance the chemical equation. Next, calculate the moles of FeBr3 that can be made from 10.0 mol of Fe. Then calculate the moles of FeBr3 that can be made from 12.0 mol of bromine. The smaller amount of FeBr3 reveals the limiting reactant.

Answer 1

Answer: The limiting reagent in the reaction is bromine.

Explanation:

Limiting reagent is defined as the reagent which is completely consumed in the reaction and limits the formation of the product.

Excess reagent is defined as the reagent which is left behind after the completion of the reaction.

Given values:

Moles of iron = 10.0 moles

Moles of bromine = 12.0 moles

The chemical equation for the reaction of iron and bromine follows:

$2Fe+3Br_2\rightarrow 2FeBr_3$

By the stoichiometry of the reaction:

If 3 moles of bromine reacts with 2 moles of iron

So, 12.0 moles of bromine will react with = $\frac{2}{3}\times 12.0=8moles$ of iron

As the given amount of iron is more than the required amount. Thus, it is present in excess and is considered as an excess reagent.

Hence, bromine is considered a limiting reagent because it limits the formation of the product.

Thus, the limiting reagent in the reaction is bromine.