Question

Slide to the correct value of x to balance the given equation.

${\mathrm{Fe}}_2{O}_3\left(s\right)+3H_2\left(g\right)\to 2\mathrm{Fe}\left(s\right)+{\mathrm{xH}}_{2}O\left(l\right)$

Answer 1

A balanced chemical equation has an equal number of atoms on both the sides of a chemical reaction.

For the given equation: ${\mathrm{Fe}}_2{O}_3\left(s\right)+3H_2\left(g\right)\to 2\mathrm{Fe}\left(s\right)+{\mathrm{xH}}_{2}O\left(l\right)$
Reactants Products

Elements	No. of atoms	Elements	No. of atoms
Fe	2	Fe	2
O	3	O	x
H	6	H	2x

Here, Fe atoms are balanced on both sides. To balance H and O atoms, the value of $x$ should be 3.

Hence, the balanced equation is ${\text{Fe}}_2{\text{O}}_3\text{(s)}+3{\text{H}}_2\text{(g)}\to 2\text{Fe(s)}+3{\text{H}}_2\text{O(l)}$