## Step 1: Identify the Substituents and Their Positions The compound shown at the top is a cyclohexane ring with two substituents: - An **isopropyl group** (–CH(CH₃)₂) at the 1-position (wedge, up) - A **methyl group** (–CH₃) at the 2-position (dash, down) **Explanation:** The stability of a cyclohexane chair conformation depends on the positions of the bulky groups. Bulky groups prefer the **equatorial** position to minimize 1,3-diaxial interactions. --- ## Step 2: Analyze the Chair Conformation Options Look for the conformation where the **isopropyl group** (largest) is **equatorial** and, if possible, the methyl group is also equatorial. If both can't be equatorial, the largest group should definitely be equatorial. - **Option B** shows the isopropyl group in the equatorial position and the methyl in the axial position. **Explanation:** The most stable chair conformation places the largest group (isopropyl) in the equatorial position to minimize steric strain, even if the smaller group (methyl) ends up axial. --- ## Final Answer **Option B** is the most stable chair conformation for the given compound.

# Determining the Most Stable Chair Conformation ## Step 1: Identify the Substituents and Their Positions The compound is a cyclohexane ring with two substituents: - An **isopropyl group** (–CH(CH₃)₂) at the 1-position (wedge, indicating it is up) - A **methyl group** (–CH₃) at the 2-position (dash, indicating it is down) **Explanation:** In cyclohexane, bulky substituents are more stable in the **equatorial** position to reduce steric strain caused by 1,3-diaxial interactions. --- ## Step 2: Analyze the Chair Conformation Options Evaluate the chair conformations for the positioning of the substituents: - The **isopropyl group** should be **equatorial** for stability. - The **methyl group** can be either axial or equatorial, but preferably equatorial if possible. **Observation:** In the proposed conformations, **Option B** places the isopropyl group in the equatorial position and the methyl group in the axial position. **Explanation:** This arrangement minimizes steric hindrance and strain, making it the most stable conformation of the compound. --- ## Final Answer **Option B** is the most stable chair conformation for the given compound.