A 200 mL sample of hard water requires 33.0 " mL of " 0.01 M `H_2SO_4` for complete neutralisation.
200 " mL of " the same sample was boiled with 15.0 " mL of " 0.1 M NaOH solution, filtered and made up to 200 mL again. This sample now requires 53.6 " mL of " 0.01 M `H_2SO_4`. Calculate Mg hardness.

Explanation

To solve the problem of calculating the magnesium hardness in the given hard water sample, we will follow these steps:

### Step 1: Calculate the equivalents of H₂SO₄ used for neutralization of the hard water sample.

Given:
- Volume of H₂SO₄ = 33.0 mL = 0.033 L
- Molarity of H₂SO₄ = 0.01 M

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