Sure, let's analyze the given chemical equation step by step to determine which statement is true. The equation given is:
[tex]\[ NH_3 + HCl \rightarrow NH_4Cl \][/tex]
1. Understanding the Components:
- [tex]\( NH_3 \)[/tex] is ammonia.
- [tex]\( HCl \)[/tex] is hydrochloric acid.
- [tex]\( NH_4Cl \)[/tex] is ammonium chloride.
2. Classification of Substances:
- Ammonia ([tex]\( NH_3 \)[/tex]): Ammonia is known as a base because it can accept a proton (H+). Specifically, it has a lone pair of electrons on the nitrogen atom that can bind to a proton.
- Hydrochloric Acid ([tex]\( HCl \)[/tex]): Hydrochloric acid is a strong acid that dissociates completely in water to release hydrogen ions (H+).
- Ammonium Chloride ([tex]\( NH_4Cl \)[/tex]): Ammonium chloride is a salt that results from the neutralization reaction between an acid and a base.
3. Reaction Mechanism:
- When [tex]\( NH_3 \)[/tex] reacts with [tex]\( HCl \)[/tex], the base [tex]\( NH_3 \)[/tex] accepts a proton from the acid [tex]\( HCl \)[/tex]. This forms the ammonium ion [tex]\( NH_4^+ \)[/tex] and the chloride ion [tex]\( Cl^- \)[/tex], which together make up the salt [tex]\( NH_4Cl \)[/tex].
4. Verifying the Statements:
- Statement 1: [tex]\( NH_3 \)[/tex] is the acid and [tex]\( NH_4Cl \)[/tex] is the salt.
- This is incorrect because [tex]\( NH_3 \)[/tex] is not an acid; it is a base.
- Statement 2: [tex]\( NH_3 \)[/tex] is the base and [tex]\( NH_4Cl \)[/tex] is the salt.
- This is correct as [tex]\( NH_3 \)[/tex] is a base that accepts a proton to form [tex]\( NH_4^+ \)[/tex], and [tex]\( NH_4Cl \)[/tex] is the resulting salt.
- Statement 3: [tex]\( HCl \)[/tex] is the acid and [tex]\( NH_3 \)[/tex] is the salt.
- This is incorrect because [tex]\( NH_3 \)[/tex] is a base, not a salt.
- Statement 4: [tex]\( HCl \)[/tex] is the base and [tex]\( NH_3 \)[/tex] is the salt.
- This is incorrect as well since [tex]\( HCl \)[/tex] is an acid, not a base, and [tex]\( NH_3 \)[/tex] is a base, not a salt.
Therefore, the correct statement is:
[tex]\[
\boxed{NH_3 \text{ is the base and } NH_4Cl \text{ is the salt.}}
\][/tex]
