Question

Which of the following statements is true for the carbonyl group?

• A. Carbon atom is sp\(^3\) hybridised
• B. Carbon atom forms three sigma bonds
• C. C-C-O bond angle is 90°
• D. The carbonyl bond is weaker as compared to the double bond in alkene

Hint:

In the carbonyl group, the carbon is sp\(^2\) hybridized, and it forms three sigma bonds, one with oxygen and two with substituent groups.

Answer 1

The Correct Option is B

Step 1: Understanding the carbonyl group.
In the carbonyl group (C=O), the carbon is sp\(^2\) hybridized and forms two sigma bonds: one with oxygen and the other with a substituent group. The third sigma bond is formed by the single bond to the other substituent group, such as a hydrogen or alkyl group.

Step 2: Analyzing the options.
(A) Carbon atom is sp\(^3\) hybridised: This is incorrect because the carbon in the carbonyl group is sp\(^2\) hybridized.
(B) Carbon atom forms three sigma bonds: This is correct. The carbon in the carbonyl group forms three sigma bonds.
(C) C-C-O bond angle is 90°: This is incorrect because the bond angle around the carbonyl carbon is about 120°, not 90°.
(D) The carbonyl bond is weaker as compared to the double bond in alkene: This is incorrect. The carbonyl bond is stronger than the double bond in an alkene due to the presence of both sigma and pi bonds.

Step 3: Conclusion.
The correct answer is (B) Carbon atom forms three sigma bonds.