See image — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

# Analysis of Hyperconjugative Stabilization **Understanding Hyperconjugation:** Hyperconjugation is the stabilization of a carbocation or alkene through delocalization of electron density from adjacent $\sigma$ bonds into an empty or partially filled orbital. ## For tert-Butyl Cation $(CH_3)_3C^+$ The carbocation has an **empty p-orbital** at the positively charged carbon. **Stabilization mechanism:** - Electrons from $\sigma$ C-H bonds of the three methyl groups donate into this empty p-orbital - This is **$\sigma \rightarrow p$ (empty)** electron delocalization - Creates resonance structures where the positive charge is distributed, lowering overall energy ## For 2-Butene $CH_3-CH=CH-CH_3$ The $\pi$ bond is already electron-rich and stable. **Stabilization mechanism:** - Electrons from $\sigma$ C-H bonds of the methyl groups adjacent to the double bond donate into the $\pi^*$ antibonding orbital - This is **$\sigma \rightarrow \pi^*$ electron delocalization** - Strengthens the C=C bond and increases stability ## Why Option A is Correct Option A correctly identifies: - $\sigma \rightarrow p$ (empty) for the carbocation - $\sigma \rightarrow \pi^*$ for the alkene **Why others fail:** - (B): Incorrect notation; $\sigma \rightarrow \sigma^*$ is not hyperconjugation - (C), (D): Don't distinguish between the two different mechanisms **Answer: (A)**