The number of carbon atoms in the parent chain when naming this compound by IUPAC is ____________.
a) 4
b) 5
c) 6
d) 7
e) None of these
Correct Answer: B (5)
This one is tricky AF.
The longest carbon chain MUST contain the parent functional group.
In this problem, the parent functional group is COOH. Any longer chain that does not include the carboxylic acid group is automatically invalid.
When named correctly, the compound is:
4-chloro-2-ethyl-3-methyl-4-pentenoic acid
This is a classic DAT trap — students chase the longest chain instead of identifying the correct parent chain.
For more DAT-level Organic Chemistry questions like this, see the 2026 DAT Destroyer, which includes many newly added problems written to reflect current DAT thinking:
2026 DAT Destroyer – High-Yield DAT Science Study Guide
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