Draw the cis and trans structures of hex-2-ene. Which isomer will have higher b.p. and why?

Explanation

To solve the question of drawing the cis and trans structures of hex-2-ene and determining which isomer has a higher boiling point, we can follow these steps:

### Step 1: Draw the Structure of Hex-2-ene
Hex-2-ene is an alkene with six carbon atoms and a double bond between the second and third carbon atoms. The molecular formula for hex-2-ene is C6H12.

The structure can be represented as follows:
```
CH3-CH=CH-CH2-CH2-CH3
```

### Step 2: Identify the Cis and Trans Isomers
Cis and trans isomers occur due to the restricted rotation around the double bond.

- **Cis Isomer**: In the cis isomer, the two substituents (in this case, the CH3 group and the hydrogen atom) on the double bond are on the same side.

The structure of the cis isomer can be represented as:
```
H CH3
\ /
C=C
/ \
CH2 CH2
| |
CH3 H
```

- **Trans Isomer**: In the trans isomer, the two substituents on the double bond are on opposite sides.

The structure of the trans isomer can be represented as:
```
H H
\ /
C=C
/ \
CH2 CH2
| |
CH3 CH3
```

### Step 3: Determine Which Isomer Has a Higher Boiling Point
To determine which isomer has a higher boiling point, we need to consider the intermolecular forces present in each isomer.

- **Cis Isomer**: The cis isomer has a net dipole moment because the polar bonds do not cancel each other out. This results in stronger dipole-dipole interactions between molecules.

- **Trans Isomer**: The trans isomer has a symmetrical structure, leading to a cancellation of dipole moments. Therefore, it has weaker dipole-dipole interactions.

### Conclusion
Since the cis isomer has stronger dipole-dipole interactions due to its net dipole moment, it will have a higher boiling point compared to the trans isomer.

### Final Answer
- **Cis Structure**:
```
H CH3
\ /
C=C
/ \
CH2 CH2
| |
CH3 H
```
- **Trans Structure**:
```
H H
\ /
C=C
/ \
CH2 CH2
| |
CH3 CH3
```
- **Higher Boiling Point**: The cis isomer has a higher boiling point due to stronger dipole-dipole interactions.