25 mL of `N/10 NaOH` solution exactly neutralise 20 mL of an acid solution. What is the normality of the acid solution ?

Explanation

To solve the problem, we need to find the normality of the acid solution using the information provided about the neutralization reaction between the NaOH solution and the acid solution.

### Step-by-Step Solution:

1. **Identify Given Values**:
- Normality of NaOH solution (N1) = \( \frac{1}{10} \) N
- Volume of NaOH solution (V1) = 25 mL
- Volume of acid solution (V2) = 20 mL
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