The `pH` of an aqueous solution of `0.1 M` solution of a weak monoprotic acid which is `1%` ionised is

Options

A. `1`
B. `2`
C. `3`
D. `11`

Explanation

To find the pH of a 0.1 M solution of a weak monoprotic acid that is 1% ionized, we can follow these steps:

### Step 1: Determine the concentration of H⁺ ions
Given that the acid is 1% ionized, we can calculate the concentration of H⁺ ions produced from the dissociation of the acid.

- The initial concentration of the acid (C) = 0.1 M
- Percentage ionization = 1%

The concentration of H⁺ ions can be calculated as:
\[ [\text{H}^+] = C \times \frac{\text{ionization percentage}}{100} = 0.1 \, \text{M} \times \frac{1}{100} = 0.001 \, \text{M} = 10^{-3} \, \text{M} \]

### Step 2: Calculate the pH
The pH of a solution is calculated using the formula:
\[ \text{pH} = -\log[\text{H}^+] \]

Substituting the value of [H⁺]:
\[ \text{pH} = -\log(10^{-3}) = 3 \]

### Final Answer
Thus, the pH of the 0.1 M solution of the weak monoprotic acid that is 1% ionized is **3**.

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