Concept:To name a branched alkane: 1) Identify the longest continuous chain. 2) Number from the end closest to the first branch. 3) Group identical substituents using multipliers (di, tri, etc.).
Solution:- Longest chain: The straight horizontal chain contains 6 carbons (hexane).
- Numbering:
- Numbering left-to-right gives branches at 2, 3, and 5 (Sum = 10).
- Numbering right-to-left gives branches at 2, 4, and 5 (Sum = 11).
- The lowest locant set is 2,3,5.
- Substituents: There are three methyl groups at positions 2, 3, and 5. This makes it "trimethyl".
- Putting it together gives 2,3,5-trimethylhexane.
Why other options are incorrect:Option A fails to identify the longest chain (6 instead of 5). Option C uses incorrect numbering (from the wrong side). Option D uses non-IUPAC branching rules.
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