The strength of a basic solution can be increased by

Options

A. by adding `H^(+)` ions
B. by decreasing `OH^(-)` ions
C. by adding OH ions
D. by reducing `H^(+)` ions

Explanation

To determine how to increase the strength of a basic solution, we need to analyze the options provided in the question. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand Basic Solutions
A basic solution is characterized by the presence of hydroxide ions (OH⁻). The strength of a basic solution is related to the concentration of these hydroxide ions.

**Hint:** Remember that basicity is associated with the concentration of OH⁻ ions in a solution.

### Step 2: Analyze the Options
We have four options to consider:
1. Adding H⁺ ions
2. Decreasing OH⁻ ions
3. Adding OH⁻ ions
4. Reducing H⁺ ions

**Hint:** Think about how each action affects the concentration of OH⁻ ions in the solution.

### Step 3: Evaluate Each Option
- **Option 1: Adding H⁺ ions**
- Adding H⁺ ions will react with OH⁻ ions to form water (H₂O), which decreases the concentration of OH⁻ ions. This will reduce the basicity of the solution.
- **Conclusion:** This option is incorrect.

- **Option 2: Decreasing OH⁻ ions**
- If we decrease the concentration of OH⁻ ions, the solution will become less basic, hence reducing its strength.
- **Conclusion:** This option is incorrect.

- **Option 3: Adding OH⁻ ions**
- Adding more OH⁻ ions directly increases the concentration of hydroxide ions in the solution, thus increasing its basicity and strength.
- **Conclusion:** This option is correct.

- **Option 4: Reducing H⁺ ions**
- While reducing H⁺ ions might seem beneficial, without sufficient OH⁻ ions present, this action alone does not guarantee an increase in basicity.
- **Conclusion:** This option is incorrect.

### Step 4: Final Conclusion
The correct way to increase the strength of a basic solution is by **adding OH⁻ ions**.

**Final Answer:** The strength of a basic solution can be increased by adding OH⁻ ions.

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