Which statement is /are correct about cyclohexene and cyclodecene?

Options

A. `Z` or `cis-` cyclohexene is more stable than `E` or transisomers.
B. `Z` or `cis-` cyclohexene is more stable than `E` or trans`-` isomer.
C. `Z` or `cis-`cyclohexene is less stable than `E` or trans `-` isomer.
D. `Z` or `cis-`cyclodecene is less stable than `E` or trans`-` isomer.

Explanation

To determine which statements are correct about cyclohexene and cyclodecene, we will analyze each statement based on the stability of the cis (Z) and trans (E) isomers of these compounds.

### Step-by-Step Solution:

1. **Understanding Cyclohexene and Cyclodecene**:
- Cyclohexene is a six-membered ring with one double bond.
- Cyclodecene is a ten-membered ring with one double bond.

2. **Analyzing the First Statement**:
- The first statement claims that Z (cis) cyclohexene is more stable than E (trans) cyclohexene.
- **Stability Analysis**:
- In the cis form, both hydrogen atoms are positioned on the same side of the double bond, which minimizes steric strain.
- In the trans form, the hydrogen atoms are on opposite sides, leading to angle strain due to the sp² hybridization of the carbons.
- **Conclusion**: This statement is correct.

3. **Analyzing the Second Statement**:
- The second statement is essentially a repetition of the first, stating that Z (cis) cyclohexene is more stable than E (trans) isomer.
- **Conclusion**: This statement is also correct.

4. **Analyzing the Third Statement**:
- The third statement claims that Z (cis) cyclohexene is less stable than E (trans) isomer.
- **Stability Analysis**:
- As established earlier, the cis form is more stable than the trans form due to reduced angle strain.
- **Conclusion**: This statement is incorrect.

5. **Analyzing the Fourth Statement**:
- The fourth statement claims that Z (cis) cyclodecene is less stable than E (trans) cyclodecene.
- **Stability Analysis**:
- In larger rings like cyclodecene, the steric strain is less pronounced compared to smaller rings. The trans form is generally more stable due to less steric hindrance.
- **Conclusion**: This statement is correct.

### Final Conclusion:
- The correct statements about cyclohexene and cyclodecene are:
- Statement 1: Correct
- Statement 2: Correct
- Statement 3: Incorrect
- Statement 4: Correct

Thus, the correct options are the first, second, and fourth statements.