See image — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

# Analysis of Structures E, F, and G **Structure Identification:** - **E**: 2,2-dimethylpropanal (ketone with $C=O$) - **F**: Enol form with $C=C$ and $OH$ group - **G**: Enediol form with $C=C$ and two $OH$ groups **Testing Each Relationship:** **E and F relationship:** $$\text{E (ketone)} \rightleftharpoons \text{F (enol)}$$ These are **tautomers** — they differ in the position of a double bond and a hydrogen atom, interconverting via a proton shift. This is classic keto-enol tautomerism. **E and G relationship:** E can also form the enediol form G: $$\text{E (ketone)} \rightleftharpoons \text{G (enediol)}$$ This is also **tautomerism** (specifically geminal diol/enediol tautomerism). **F and G relationship:** F and G are **not** tautomers of each other — they're both enolic forms with different structures. **Why other options fail:** - **(A)** E, F, G are not resonance structures (resonance requires same atom connectivity; these change bonding) - **(C)** F and G aren't geometric isomers (same atoms in different geometric arrangements around a double bond) - **(D)** F and G aren't diastereomers (not stereoisomers with differing configurations) **Answer: (B)** E and F are tautomers, AND E and G are tautomers. ✓