Read the scenario.

Ammonia is obtained from a reaction between nitrogen and hydrogen gases. The mole ratio between hydrogen gas and nitrogen gas is 3 to 1, and the mole ratio between ammonia and hydrogen gases is 2 to 3.

What is the chemical equation of the synthesis reaction of ammonia?

3N2 (g) + H2 (g) → 2NH3 (g)

N2 (g) + 3H2 (g) → 2NH3 (g)

3N2 (g) + 3H2 (g) → 2NH3 (g)

N2 (g) + 2H2 (g) → 2NH3 (g)

The chemical equation of the synthesis reaction of ammonia is

N₂ (g) + 3 H₂ (g) → 2 NH₃ (g)

Explanation:

Molar ratio is the ratio of number of moles between any two elements in the reactants side or in between reactant and product side.

Like, in the present situation, it is stated that the molar ratio between hydrogen gas and nitrogen gas is 3 : 1. This means 3 number of hydrogen molecules and 1 number of nitrogen molecule are required to form the product ammonia.

Since, it is known that two hydrogen atoms will make a single hydrogen molecule, so 3 number of hydrogen molecules means, 3 H₂ is one of the reactant. Similarly, two nitrogen atoms can make a single nitrogen molecule, so N₂ is another reactant. Thus the two reactants are obtained as 3 H₂ and N₂.

Now, it is also stated that the molar ratio between ammonia (NH₃) and hydrogen gas (H₂) is 2 : 3. This means 2 number of ammonia molecules are present in the product side. And we know that 3 number of hydrogen molecules are present in the reactant side.

Thus, the chemical equation of the synthesis reaction of ammonia is

N₂ (g) + 3 H₂ (g) → 2 NH₃ (g)