Question

Which of the following statements is correct regarding homologous series?

• A. It has same functional group and the successive members differ by \(-\text{CH}_{2}-\)group.
• B. It possesses the same physical properties.
• C. It has compounds with the same number of carbon atoms.
• D. It has members of various functional groups.

Hint:

Members of a homologous series have the same functional group and differ successively by a CH2 unit.

Answer 1

The Correct Option is A

Step 1: Recall the definition
Same functional group, similar chemistry, and a $\text{CH}_2$ difference between neighbours.

Step 2: Test option (B)
Physical properties change gradually, so they are not the same.

Step 3: Test options (C) and (D)
Carbon number changes by one each step and the functional group is common, so these fail. Option (A) stands.

Final Answer:
Only the first statement matches the definition of a homologous series. \[ \boxed{\text{(A) }\text{It has same functional group and the successive members differ by }-\text{CH}_{2}-\text{ group.}} \]