The formula of green vitriol is

Options

A. `FeSO_4 cdot 7H_2O`
B. `MgSO_4 cdot 7H_2O`
C. `ZnSO_4 cdot 7H_2O`
D. `CuSO_4 cdot 5H_2O`

Answer

To determine the formula of green vitriol, we can follow these steps:

### Step 1: Understand what green vitriol is
Green vitriol is a common name for a specific chemical compound. It is important to identify the chemical composition of this compound.

### Step 2: Identify the chemical formula
Green vitriol is known to be a hydrated form of iron(II) sulfate. The chemical formula for iron(II) sulfate is FeSO4. When it is hydrated, it includes water molecules.

### Step 3: Determine the number of water molecules
The specific hydrated form of iron(II) sulfate that is referred to as green vitriol contains 7 water molecules. Therefore, the complete formula for green vitriol is FeSO4·7H2O.

### Step 4: Choose the correct option
From the provided options, the correct formula for green vitriol is:
- FeSO4·7H2O

### Final Answer:
The formula of green vitriol is **FeSO4·7H2O**.

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