A : Magnesium sulphate is heptahydrate where as calcium sulphate is dihydrate.
R : Mg and Ca belongs to Group II.

Options

A. If both Assertion & Reason are true and the reason is the correct explanantion of the assertion, then mark (1).
B. If both Assertion & Reason are true and the reason is not the correct explanantion of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false. Them mark (3).
D. If both Assertion and reason are false statement, then mark (4).

Answer

To analyze the assertion and reason provided in the question, we will break it down step by step.

### Step 1: Understanding the Assertion
The assertion states that magnesium sulfate is a heptahydrate, while calcium sulfate is a dihydrate.

- **Magnesium Sulfate (MgSO₄)**: The heptahydrate form of magnesium sulfate is represented as MgSO₄·7H₂O. This means that there are 7 water molecules associated with each formula unit of magnesium sulfate.
- **Calcium Sulfate (CaSO₄)**: The dihydrate form of calcium sulfate is represented as CaSO₄·2H₂O, indicating that there are 2 water molecules associated with each formula unit of calcium sulfate.

### Step 2: Understanding the Reason
The reason states that magnesium (Mg) and calcium (Ca) belong to Group II of the periodic table.

- **Group II Elements**: Both magnesium and calcium are alkaline earth metals, which are found in Group II of the periodic table. They have similar chemical properties due to their position in the same group.

### Step 3: Evaluating the Relationship Between Assertion and Reason
Now we need to determine if the reason correctly explains the assertion.

- While it is true that both magnesium and calcium are in Group II, this does not directly explain why magnesium sulfate is a heptahydrate and calcium sulfate is a dihydrate. The difference in the number of water molecules associated with these salts is more related to their ionic sizes and the ability of the cations to stabilize water molecules around them.

### Conclusion
The assertion is true: magnesium sulfate is indeed a heptahydrate, and calcium sulfate is a dihydrate. However, the reason provided is not a correct explanation for the assertion. The reason does not adequately explain the difference in hydration between the two compounds.

### Final Answer
- **Assertion (A)**: True
- **Reason (R)**: False
- Therefore, the correct relationship is that the assertion is true, but the reason is not a correct explanation.

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