If the pH of a solution is 4.0 a `25^(@)C`, its pOH would be `(K_(w) = 10^(-14))`

Options

A. `4.0`
B. `6.0`
C. `8.0`
D. `10.0`

Explanation

To find the pOH of a solution when the pH is given, we can use the relationship between pH and pOH, which states that:

\[ \text{pH} + \text{pOH} = 14 \]

### Step-by-Step Solution:

1. **Identify the given value**:
- We are given that the pH of the solution is 4.0.

2. **Use the pH and pOH relationship**:
- According to the formula, we can rearrange it to find pOH:
\[ \text{pOH} = 14 - \text{pH} \]

3. **Substitute the given pH value**:
- Now, substitute the value of pH into the equation:
\[ \text{pOH} = 14 - 4.0 \]

4. **Calculate pOH**:
- Performing the subtraction gives:
\[ \text{pOH} = 10.0 \]

5. **Final Answer**:
- Therefore, the pOH of the solution is 10.0.

### Summary:
The pOH of the solution is 10.0 when the pH is 4.0.

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