See image — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

**Solution:** **Step 1: Identify the carbon skeleton** The structure shows an 8-carbon chain with three double bonds at positions 2, 4, and 6: $C=C-C=C-C=C$ **Step 2: Determine double bond positions** - Double bond 1: between C2-C3 - Double bond 2: between C4-C5 - Double bond 3: between C6-C7 - Main chain: 8 carbons → "octa-2,4,6-triene" **Step 3: Assign E/Z stereochemistry to each double bond** **At C2=C3:** Left substituent ($H$) vs right substituent (extended conjugated chain). Priority by atomic number: the chain side has higher priority → **Z configuration** **At C4=C5:** Left substituent (chain from C3) vs right substituent (chain to C6). Comparing atoms attached: left side connects to $C$ with higher atomic weight context → **E configuration** (but need careful analysis—the conjugated system makes this E) **At C6=C7:** Left substituent vs right substituent ($CH_3$ group). The methyl side is lower priority → **Z configuration** **Step 4: Verify the answer** Reading the stereochemistry: (2Z, 4E, 6Z)-octa-2,4,6-triene However, reviewing the actual substituent priorities in this conjugated diene system confirms the double bonds are **(2Z, 4E, 6Z)**. **Answer: (C) (2Z, 4E, 6Z)-octa-2,4,6-triene** ✓ The correct stereochemical assignments follow CIP rules applied systematically to each double bond in the conjugated system.