Question

Calculate the rate of iron at which will be converted into its oxide by action of $18$ gram of steam $Fe + {H_2}O\xrightarrow{\Delta }F{e_3}{O_4} + {H_2}$?

Answer 1

Hint: The amount of steam produced is given in the question. It can be used to find the amount of iron required to produce the required amount of steam. We have to balance the given chemical equation to get the coefficients of iron and steam.

Complete answer:
To solve this question, we have to balance the given chemical reaction first. To balance any chemical reaction, we have to make sure that the number of atoms of each element are equal in both reactant and product side. The hydrogen and oxygen atoms should be balanced after balancing all the other atoms. Here, there are three iron atoms on the product side. So add coefficient $3$ before iron on the reactant side. There are four oxygen atoms on the product side. So add coefficient $4$ before water on the reactant side. There are eight hydrogen atoms on the reactant side. So add coefficient $4$ before hydrogen in the product side. The balanced chemical equation is as follows: $3Fe + 4{H_2}O\xrightarrow{\Delta }F{e_3}{O_4} + 4{H_2}$.
$4$ moles of steam are needed to convert $3$ moles of iron into its oxide.
So, $1$ mole of steam can convert $\dfrac{3}{4}$ moles of iron into its oxide.
We know that $1$ mole of steam$ = 18$g of ${H_2}O$
$1$ mole of iron$ = 56$g of iron
So, $18$g of ${H_2}O$ will convert$ = \dfrac{3}{4} \times 56$g of iron into its oxide
i.e. $42$g of iron.
Therefore, $18$g of ${H_2}O$ will convert $42$g of iron into its oxide.

Note:
Remember to balance the given chemical reaction before solving problems of this type. Without balancing the given chemical reaction, we cannot get the mole ratio which is essential to solve these types of problems.