How much water should be added to `3M HCl` solution to form
`1"litre"` of `0.5M HCl` ?

Explanation

To solve the problem of how much water should be added to a `3M HCl` solution to form `1 litre` of `0.5M HCl`, we can follow these steps:

### Step 1: Understand the relationship between molarity, volume, and moles
We know that molarity (M) is defined as the number of moles of solute divided by the volume of solution in liters. Therefore, we can use the formula:

\[ M_1 \times V_1 = M_2 \times V_2 \]

where:
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