Calculate the hardness of water sample which contains 0.001 mole of `MgSO_4` dissolved per litre of water.

Explanation

To calculate the hardness of a water sample containing 0.001 moles of MgSO₄ dissolved per liter, we will follow these steps:

### Step 1: Determine the equivalent of MgSO₄ in terms of CaCO₃
The hardness of water is commonly expressed in terms of equivalent CaCO₃. Each mole of MgSO₄ contributes to the hardness as if it were CaCO₃.

Given:
- Moles of MgSO₄ = 0.001 moles

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