Consider the following salts. Which one(s) when dissolved in water will produce a basic solution?
1. `RbClO_(4)` , 2. `NaNO_(2)` , 3. `NH_(4)Cl` , 4. `NaCl`

Options

A. 1 and 3
B. only 3
C. 1 and 2
D. 3 and 4

Answer

To determine which of the given salts will produce a basic solution when dissolved in water, we need to analyze each salt based on the strength of the acids and bases from which they are derived.

### Step-by-Step Solution:

1. **Identify the salts and their components**:
- **RbClO₄**: This salt is derived from rubidium hydroxide (RbOH, a strong base) and perchloric acid (HClO₄, a strong acid).
- **NaNO₂**: This salt is derived from sodium hydroxide (NaOH, a strong base) and nitrous acid (HNO₂, a weak acid).
- **NH₄Cl**: This salt is derived from ammonium hydroxide (NH₄OH, a weak base) and hydrochloric acid (HCl, a strong acid).
- **NaCl**: This salt is derived from sodium hydroxide (NaOH, a strong base) and hydrochloric acid (HCl, a strong acid).

2. **Determine the nature of the solutions produced**:
- **RbClO₄**: Since both the acid (HClO₄) and base (RbOH) are strong, the solution will be neutral. Thus, it does not produce a basic solution.
- **NaNO₂**: The salt is derived from a weak acid (HNO₂) and a strong base (NaOH). When dissolved, it will produce a basic solution because the weak acid does not completely dissociate, leaving excess hydroxide ions (OH⁻) in the solution.
- **NH₄Cl**: This salt is derived from a strong acid (HCl) and a weak base (NH₄OH). The solution will be acidic because the strong acid will dominate, leading to a decrease in pH.
- **NaCl**: This salt is derived from a strong acid (HCl) and a strong base (NaOH). The solution will be neutral, as both components completely neutralize each other.

3. **Conclusion**:
- The only salt that produces a basic solution when dissolved in water is **NaNO₂**.

### Final Answer:
The salt that will produce a basic solution when dissolved in water is **NaNO₂** (option 2).