Question

Which from following statements is NOT true about homologous series?

• A. Each member of a series has same functional group.
• B. Each member has same type of carbon skeleton.
• C. Each member differs by ethylene group from next member.
• D. All members of series possess similar chemical properties.

Hint:

Successive members of a homologous series differ by a methylene (\(\text{CH}_2\)) group.

Answer 1

The Correct Option is C

Step 1: Check with an example
Methane $\text{CH}_4$, ethane $\text{C}_2\text{H}_6$, propane $\text{C}_3\text{H}_8$. Each step adds one carbon and two hydrogens.

Step 2: Conclude
That addition is $\text{CH}_2$, so the claim about an ethylene ($\text{C}_2\text{H}_4$) difference is incorrect. Statements A, B and D are standard properties.

Final Answer:
Statement (C) is not true; the common difference is $\text{CH}_2$. \[ \boxed{\text{(C)}} \]