Most fertilizers contain ammonia (NH3).

Most fertilizers contain ammonia (NH3). Ammonia forms when hydrogen reacts with nitrogen. Which equation correctly represents the chemical reaction that forms ammonia?
A. 3H2+N2→NH3
B. H2+N2→2NH3
C. H2+N2→NH3
​D. 3H2+N2→2NH3

The Correct Answer and Explanation is:

The correct answer is:

D. 3H₂ + N₂ → 2NH₃

Explanation:

This equation represents the chemical reaction known as the Haber process, where nitrogen (N₂) and hydrogen (H₂) gases react to form ammonia (NH₃). The balanced chemical equation is essential in understanding the exact quantities of each reactant involved to form a specific product.

Step-by-Step Balancing of the Reaction:

1. Identify the Reactants and Products:

• The reactants in this reaction are nitrogen (N₂) and hydrogen (H₂).
• The product of the reaction is ammonia (NH₃).

1. Write the Initial Unbalanced Equation:

• The reaction is written as: H₂ + N₂ → NH₃.
• However, this form does not reflect the proper stoichiometric balance.

1. Balance Nitrogen Atoms:

• Each molecule of nitrogen (N₂) contains two nitrogen atoms, while each molecule of ammonia (NH₃) contains only one nitrogen atom.
• To balance nitrogen atoms, we place a coefficient of 2 in front of NH₃, making the equation: H₂ + N₂ → 2NH₃.

1. Balance Hydrogen Atoms:

• Now, each molecule of NH₃ has three hydrogen atoms, so with 2 molecules of NH₃, there are 2 × 3 = 6 hydrogen atoms.
• To supply 6 hydrogen atoms, we need 3 molecules of H₂ (since each H₂ molecule contains 2 hydrogen atoms).
• This gives us the balanced equation: 3H₂ + N₂ → 2NH₃.

Significance of the Balanced Equation:

This balanced reaction, 3H₂ + N₂ → 2NH₃, demonstrates the law of conservation of mass, where the number of each type of atom on the reactants side is equal to that on the products side. It tells us that three molecules of hydrogen gas react with one molecule of nitrogen gas to produce two molecules of ammonia. This balanced reaction is necessary for practical applications in agriculture, as ammonia is a key component of many fertilizers, providing essential nitrogen that helps plants grow.