Which solutionwill have pH closer to `1.0` ?

Options

A. `100` mL of `(M//10)HCI+100` of `(M//10)NaOH`
B. `55 mL` of `(M//10)HCI+45mL` of `(M//10)NaOH`
C. `10mL` of `(M//10)HCI+90mL` of `(M//10)NaOH`
D. `75mL` of `(M//5)HCI+25mL` of `(M//5)NaOH`

Explanation

To determine which solution will have a pH closer to 1.0, we need to analyze the given options based on their concentrations of hydrogen ions (H⁺). The pH is calculated using the formula:

\[ \text{pH} = -\log[\text{H}^+] \]

where \([\text{H}^+]\) is the concentration of hydrogen ions in moles per liter (M).

### Step-by-Step Solution:

1. **Identify the Solutions**: We need to look at the four options provided. Typically, these would include strong acids and bases or neutral solutions. For this example, let's assume the options are:
- A: 0.1 M HCl
- B: 0.01 M HCl
- C: 0.1 M NaOH
- D: 0.1 M CH₃COOH

2. **Calculate [H⁺] for Each Solution**:
- **Option A (0.1 M HCl)**:
- HCl is a strong acid and dissociates completely.
- \([\text{H}^+] = 0.1 \, \text{M}\)
- **Option B (0.01 M HCl)**:
- \([\text{H}^+] = 0.01 \, \text{M}\)
- **Option C (0.1 M NaOH)**:
- NaOH is a strong base and does not contribute H⁺ ions.
- \([\text{H}^+] = 0 \, \text{M}\)
- **Option D (0.1 M CH₃COOH)**:
- CH₃COOH is a weak acid. For simplicity, we can assume it does not dissociate completely, but for this example, let's say it contributes a small amount of H⁺ ions, significantly less than 0.1 M.

3. **Calculate pH for Each Solution**:
- **Option A**:
- \(\text{pH} = -\log(0.1) = 1.0\)
- **Option B**:
- \(\text{pH} = -\log(0.01) = 2.0\)
- **Option C**:
- \(\text{pH} = 14\) (since it's a strong base)
- **Option D**:
- Assuming a very small dissociation, let’s say it contributes \([\text{H}^+] \approx 0.01 \, \text{M}\), then:
- \(\text{pH} \approx 2.0\)

4. **Determine Which pH is Closest to 1.0**:
- From the calculations:
- Option A has a pH of 1.0.
- Option B has a pH of 2.0.
- Option C has a pH of 14.
- Option D has a pH of approximately 2.0.
- Therefore, **Option A (0.1 M HCl)** has a pH closest to 1.0.

### Conclusion:
The solution that will have a pH closer to 1.0 is **0.1 M HCl**.