The volume of water required to prepare one litre of 0.1 N `HNO_3` solution from 10 ml of 10 N `HNO_3` solution is:

Explanation

To solve the problem of how much water is required to prepare one liter of a 0.1 N HNO3 solution from 10 ml of a 10 N HNO3 solution, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Normality-Volume Relationship**:
We will use the formula \( N_1 V_1 = N_2 V_2 \), where:
- \( N_1 \) = initial normality (10 N)
- \( V_1 \) = initial volume (10 ml)
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