What is the formula of hydrated blue copper sulphate crystal?

Options

A. `CuSO_(4).5H_(2)O`
B. `CuSO_(4).6H_(2)O`
C. `CuSO_(4).7H_(2)O`
D. `CusO_(4).8H_(2)O`

Answer

To determine the formula of hydrated blue copper sulfate crystal, we can follow these steps:

### Step 1: Identify the base compound
The base compound we are dealing with is copper sulfate, which has the formula CuSO4.

### Step 2: Understand hydration
Hydrated copper sulfate crystals contain water molecules in their structure. The number of water molecules associated with the copper sulfate can vary.

### Step 3: Analyze the options
The options given are:
1. CuSO4.5H2O
2. CuSO4.6H2O
3. CuSO4.7H2O
4. CuSO4.8H2O

### Step 4: Determine the correct number of water molecules
Hydrated copper sulfate, commonly known as blue copper sulfate, specifically contains five water molecules. This is based on the coordination chemistry of the copper ion (Cu²⁺) and its ability to coordinate with ligands, such as water molecules.

### Step 5: Write the final formula
The correct formula for hydrated blue copper sulfate crystal is therefore CuSO4.5H2O.

### Final Answer:
The formula of hydrated blue copper sulfate crystal is **CuSO4.5H2O**.

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