Question

Which from the following aldehydes contains two \(-\text{CHO}\) groups in a molecule?

• A. Acrolein
• B. O-Tolualdehyde
• C. Phthaldehyde
• D. Butyraldehyde

Hint:

Phthaldehyde is benzene-1,2-dicarbaldehyde, so it has two CHO groups.

Answer 1

The Correct Option is C

Step 1: Name Clue:
The prefix "phth-" refers to benzene-1,2-dicarboxylic derivatives, such as phthalic acid. The aldehyde version is phthaldehyde with two CHO groups.

Step 2: Others:
Acrolein, o-tolualdehyde and butyraldehyde each have one CHO group.

Step 3: Answer:
Option (C).

Final Answer:
Option (C). \[ \boxed{\text{(C) Phthaldehyde}} \]