Question

Assertion (A): Carbon can form $p\pi - p\pi$ bonds with itself and with other small sized and highly electronegative atoms.
Reason (R): Other heavier elements of group 14 can also form $p\pi - p\pi$ bonds.
Choose the correct option:

• A. Both (A) and (R) are correct and R is the correct explanation of A
• B. Both (A) and (R) are correct, but R is not the correct explanation of A
• C. (A) is correct but (R) is not
• D. (A) is not correct but (R) is correct

Hint:

$p\pi - p\pi$ multiple bonding is strongest for carbon due to its small size and good p orbital overlap; heavier elements rarely form stable multiple bonds.

Answer 1

The Correct Option is C

Step 1: Analyze Assertion (A).
Carbon, being small and highly electronegative, can form strong $p\pi - p\pi$ multiple bonds with itself (C=C, C≡C) and with other small electronegative elements like N and O. This is due to good overlap of p orbitals.

Step 2: Analyze Reason (R).
Heavier group 14 elements (Si, Ge, Sn) have larger atomic size and their p orbitals overlap poorly. Therefore, they cannot effectively form $p\pi - p\pi$ bonds.

Step 3: Compare A and R.
While A is correct, R is factually incorrect because heavier group 14 elements cannot form stable $p\pi - p\pi$ bonds. Hence, R cannot be the explanation for A.

Step 4: Conclusion.
(A) is correct but (R) is not correct.

Step 5: Final answer.
\[ \boxed{\text{Option (3)}} \]