Assertion : He and Ne do no form any clathrates
Reason : Both He and Ne are very small in size

Options

A. If both (A) and (R ) are correct and (R ) is the correct explanation of (A)
B. If both (A) and (R ) are correct,but (R ) is the correct explanation of (A)
C. If (A) is correct but (R ) is incorrect
D. If (A) is incorrect but (R ) is correct

Answer

To analyze the assertion and reason provided in the question, we can break down the solution into the following steps:

### Step 1: Understand the Assertion
The assertion states that helium (He) and neon (Ne) do not form any clathrates. Clathrates are compounds where gas molecules are trapped within a lattice of another substance, typically a solid.

### Step 2: Define Clathrates
Clathrates are formed when small gas molecules occupy the voids in a crystal lattice. The ability of a gas to form clathrates depends on its size and the size of the voids in the lattice.

### Step 3: Analyze the Sizes of He and Ne
Helium and neon are noble gases with relatively small atomic radii compared to other noble gases like argon, krypton, and xenon. The small size of He and Ne means they cannot effectively occupy the larger voids in the crystal lattice required to form stable clathrates.

### Step 4: Evaluate the Reason
The reason states that both helium and neon are very small in size. This is true and directly relates to the assertion, as their small size is the reason they do not form clathrates.

### Step 5: Conclusion
Both the assertion and the reason are correct. The reason provided is a valid explanation for the assertion. Therefore, we can conclude that the assertion is true, and the reason is true, and the reason correctly explains the assertion.

### Final Answer
- **Assertion**: True (He and Ne do not form clathrates)
- **Reason**: True (Both He and Ne are very small in size)
- **Conclusion**: The reason is the correct explanation for the assertion.

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