Ammonia is commonly used as a fertilizer for plants. It is made when nitrogen gas and hydrogen gas react under specific conditions.

Question

Consider the following reaction:
1 molecule of nitrogen (N2) reacts with 3 molecules of hydrogen (H2) to produce some amount of ammonia (NH3).
To find the amount of ammonia produced, first determine the number of each type of atom in the products.
Hint: During a chemical reaction, atoms are not created, destroyed, or changed from one chemical element to another.
Chemical element Number of atoms in reactants Number of atoms in products
H 6
N 2

Answer 1

To analyze the reaction where nitrogen gas (\( \text{N}_2 \)) reacts with hydrogen gas (\( \text{H}_2 \)) to form ammonia (\( \text{NH}_3 \)), let’s first look at the balanced chemical equation:

\[ \text{N}_2 + 3\text{H}_2 \rightarrow 2\text{NH}_3 \]

From this balanced equation, we can determine the number of atoms in the reactants and products.

Reactants:

• Nitrogen (\( \text{N}_2 \)):
  1 molecule of \( \text{N}_2 \) contains 2 nitrogen atoms.
  Total nitrogen atoms in reactants: 2

• Hydrogen (\( \text{H}_2 \)):
  3 molecules of \( \text{H}_2 \) contain 3 × 2 = 6 hydrogen atoms.
  Total hydrogen atoms in reactants: 6

Summary of Reactants:

• Number of atoms in reactants:
  • N: 2
  • H: 6

Products:

According to the balanced equation, 2 molecules of ammonia (\( \text{NH}_3 \)) are produced:

• Each molecule of \( \text{NH}_3 \) contains 1 nitrogen atom and 3 hydrogen atoms.
• Therefore, for 2 molecules of \( \text{NH}_3 \):
  • Total nitrogen atoms = 2 × 1 = 2
  • Total hydrogen atoms = 2 × 3 = 6

Summary of Products:

• Number of atoms in products:
  • N: 2
  • H: 6

Final Summary:

| Chemical element | Number of atoms in reactants | Number of atoms in products | |------------------|------------------------------|------------------------------| | H | 6 | 6 | | N | 2 | 2 |

Thus, the numbers of each type of atom are conserved in the reaction, which aligns with the law of conservation of mass.