Which one of the following is the formula of a salt?

Options

A. HCl
B. NaCl
C. `H_(2)SO_(4)`
D. `NH_(4)OH`

Answer

To determine which of the given options is the formula of a salt, we need to understand what a salt is and how it is formed. A salt is typically formed from the neutralization reaction between an acid and a base, resulting in the formation of salt and water.

### Step-by-Step Solution:

1. **Understand the Definition of Salt**:
- A salt is a compound formed from the reaction of an acid and a base. This reaction is known as neutralization.

2. **Identify the Components of the Reaction**:
- In a neutralization reaction, an acid (like HCl) reacts with a base (like NaOH) to produce a salt (like NaCl) and water (H2O).

3. **Analyze the Given Options**:
- We need to check the formulas provided in the options to see which one represents a salt.

4. **Examine Each Option**:
- **NaCl (Sodium Chloride)**: This is formed from the reaction of hydrochloric acid (HCl) and sodium hydroxide (NaOH). Therefore, NaCl is a salt.
- **HCl (Hydrochloric Acid)**: This is an acid, not a salt.
- **H2SO4 (Sulfuric Acid)**: This is also an acid, not a salt.
- **NH4OH (Ammonium Hydroxide)**: This is a base, not a salt.

5. **Conclusion**:
- Among the options, NaCl is the only one that is a salt, as it is formed from the neutralization reaction of an acid and a base.

### Final Answer:
The formula of a salt is **NaCl** (Sodium Chloride).

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