Define hyperconjugation by taking an example of propene.

Answer

**Step-by-Step Solution:**

1. **Definition of Hyperconjugation:**
Hyperconjugation is defined as the interaction of electrons in a sigma bond (usually C-H or C-C bonds) with adjacent empty or partially filled non-bonding p-orbitals, or with anti-bonding sigma or pi-orbitals. This interaction leads to the delocalization of electrons, resulting in an extended molecular orbital that increases the stability of the molecule.

2. **Example of Propene:**
Let's take propene (C3H6) as an example. The structure of propene can be represented as:
\[ \text{CH}_2= \text{CH}-\text{CH}_3 \]
In this structure, we have a double bond between the first two carbon atoms (C1 and C2) and a single bond between C2 and C3.

3. **Identification of Sigma Bonds:**
In propene, the sigma bonds are formed between:
- C1 and C2 (C-H and C-C bonds)
- C2 and C3 (C-H and C-C bonds)

4. **Hyperconjugation in Propene:**
The hyperconjugation effect can be illustrated by considering the C-H sigma bonds adjacent to the double bond. The electrons in the C-H sigma bond of the CH3 group (C3) can interact with the empty p-orbital of C2 (which is involved in the double bond).

5. **Bond Shifting:**
When we consider the hyperconjugation effect, we can visualize the shifting of electrons:
- The C-H bond from the CH3 group can "donate" its electron density to the adjacent empty p-orbital of C2. This results in the formation of a new resonance structure where the double bond can shift, leading to a more stable configuration.

6. **Resonance Structures:**
The resonance structures that can be formed through hyperconjugation include:
- One structure where the C-H bond from the CH3 group interacts with the double bond, leading to a positive charge on C2.
- Another structure where the double bond shifts to C1, resulting in a different arrangement of bonds and charges.

7. **Conclusion:**
The delocalization of electrons through hyperconjugation in propene increases the stability of the molecule. The more hyperconjugating structures that can be formed, the greater the stability of the propene system.

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