Question

Write down the steps in balancing the equation \[\ce{N2(g) + H2(g) <=> NH3(g)}\]

Answer 1

Step 1: Rewrite the given equation as it is

\[\ce{N2(g) + H2(g) <=> NH3(g)}\]

Step 2:

On both sides of the equation, write the number of atoms of each element in the imbalanced equation.

Element	Number of atoms in reactants	Number of atoms in products
N	2	1
H	2	3

Step 3:

In the equation provided. The element hydrogen is present in the compound NH3. There are two H atoms on the left and three H atoms on the right. H atoms should be equal on both sides.

Hydrogen atoms	In reactants	In products
Initially	2	3
To balance	3 × 2	2 × 3

We use two as the factor in the products and three as the factor in the reactants to equalise the number of hydrogen atoms. The equation now becomes

\[\ce{N2 + 2H2 -> 2NH3}\]

Count each element's atoms on both sides of the equation now. Both sides have an equal number of atoms. Therefore, the equation that is balanced is

\[\ce{N2 + 2H2 -> 2NH3}\]

Now indicate the physical states of the reactants and products

\[\ce{N2(g) + 3H2(g) <=> 2NH3(g)}\]