To determine which equation correctly represents the chemical reaction that forms ammonia, we'll need to consider the balanced chemical equation for the formation of ammonia from nitrogen and hydrogen. The formation of ammonia involves the reaction of nitrogen gas (N₂) with hydrogen gas (H₂).
Let's start by writing the reactants and products:
- Nitrogen gas ([tex]$N_2$[/tex])
- Hydrogen gas ([tex]$H_2$[/tex])
- Ammonia ([tex]$NH_3$[/tex])
The balanced chemical equation follows the principle that the number of atoms of each element on the reactants side must be equal to the number of atoms on the products side.
The balanced equation for the synthesis of ammonia is:
[tex]\[ N_2 + 3 H_2 \rightarrow 2 NH_3 \][/tex]
Let's verify this step-by-step:
1. Reactants:
- [tex]\( N_2 \)[/tex]: 1 molecule containing 2 nitrogen atoms.
- [tex]\( 3 H_2 \)[/tex]: 3 molecules, each containing 2 hydrogen atoms, thus a total of [tex]\( 3 \times 2 = 6 \)[/tex] hydrogen atoms.
2. Products:
- [tex]\( 2 NH_3 \)[/tex]: 2 molecules, each containing 1 nitrogen atom and 3 hydrogen atoms.
Now let's count the atoms on the product side:
- Nitrogen atoms: [tex]\( 2 \times 1 = 2 \)[/tex] nitrogen atoms.
- Hydrogen atoms: [tex]\( 2 \times 3 = 6 \)[/tex] hydrogen atoms.
The number of each type of atoms on both sides matches, confirming that the equation is balanced.
Comparing the given options to the balanced equation:
A. [tex]\( HH_2 + N_2 \rightarrow NH_3 \)[/tex] - This is not a proper representation due to incorrect molecular representation.
B. [tex]\( H_2 + N_2 \rightarrow 2 NH_3 \)[/tex] - The hydrogen atoms are not balanced (only 2 H's on the reactants side, but 6 H's on the products side).
C. [tex]\( H_2 + N_2 \rightarrow NH_3 \)[/tex] - Neither nitrogen nor hydrogen atoms are balanced.
D. [tex]\( 3 H_2 + N_2 \rightarrow 2 NH_3 \)[/tex] - This matches the balanced chemical equation exactly.
Therefore, the correct equation that represents the formation of ammonia is:
D. [tex]\( 3 H_2 + N_2 \rightarrow 2 NH_3 \)[/tex]
Thus, the correct answer is [tex]\( \boxed{4} \)[/tex], which corresponds to choice [tex]\( D \)[/tex].
