Which does not show resonance

Options

A. Benzene
B. Aniline
C. Ethyl amine
D. Toluene

Explanation

To determine which compound does not show resonance, we need to analyze the structures of the given compounds and identify whether they have conjugated double bonds that can allow for resonance.

### Step-by-Step Solution:

1. **Understand Resonance**:
Resonance occurs when a molecule can be represented by two or more valid Lewis structures (resonance structures) that differ only in the placement of electrons. These structures contribute to the overall hybrid structure of the molecule.

2. **Identify Conjugation**:
Conjugation involves alternating single and double bonds, allowing for the delocalization of electrons. For resonance to occur, there must be at least one double bond adjacent to a single bond.

3. **Analyze Benzene**:
Benzene (C6H6) has alternating double bonds, which allows for resonance. The electrons in the double bonds can be delocalized over the entire ring structure, leading to multiple resonance forms.

4. **Analyze Aniline**:
Aniline (C6H5NH2) has a phenyl group (benzene) attached to an amine group. The presence of the benzene ring allows for resonance due to the alternating double bonds in the ring.

5. **Analyze Ethyl Amine**:
Ethyl amine (C2H5NH2) has a nitrogen atom bonded to two carbon atoms and does not have any double bonds. Since there are no conjugated double bonds present, there is no possibility for resonance.

6. **Analyze Toluene**:
Toluene (C7H8) has a methyl group attached to a benzene ring. The benzene part allows for resonance due to its conjugated double bonds.

7. **Conclusion**:
Among the compounds analyzed, ethyl amine does not show resonance because it lacks the necessary conjugated double bonds.

### Final Answer:
Ethyl amine does not show resonance.