How many moles of `H_(2)O` are liberated when one mole hydrated `MgCl_(2)` is heated?

Options

A. 6
B. 5
C. 4
D. 3

Explanation

To determine how many moles of water (H₂O) are liberated when one mole of hydrated magnesium chloride (MgCl₂·6H₂O) is heated, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the formula of hydrated MgCl₂**:
The hydrated form of magnesium chloride is represented as MgCl₂·6H₂O. This indicates that each formula unit of MgCl₂ is associated with six water molecules.

2. **Understand the thermal decomposition reaction**:
When MgCl₂·6H₂O is heated, it undergoes thermal decomposition. The general reaction can be written as:
\[ \text{MgCl}_2 \cdot 6\text{H}_2\text{O} \rightarrow \text{MgO} + 2\text{HCl} + 6\text{H}_2\text{O} \]

3. **Count the moles of water produced**:
From the balanced equation, we can see that for every 1 mole of MgCl₂·6H₂O that is heated, 6 moles of water (H₂O) are produced.

4. **Conclusion**:
Therefore, when 1 mole of hydrated MgCl₂ is heated, it liberates 6 moles of water.

### Final Answer:
When one mole of hydrated MgCl₂ is heated, **6 moles of H₂O are liberated**.

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