`C-C` bond length is maximum in

Options

A. diamond
B. graphite
C. naphthalene
D. fullerene

Explanation

To determine which compound has the maximum carbon-carbon (C-C) bond length among diamond, graphite, naphthalene, and fullerene, we need to analyze the bonding characteristics and structures of each compound.

### Step-by-Step Solution:

1. **Understanding Diamond:**
- Diamond consists of carbon atoms arranged in a tetrahedral structure.
- Each carbon atom is sp³ hybridized and forms four sigma bonds with neighboring carbon atoms.
- The C-C bond length in diamond is approximately **154 picometers**.

2. **Understanding Graphite:**
- Graphite has a layered structure where each carbon atom is bonded to three other carbon atoms.
- The bonding is sp² hybridized, resulting in the formation of sigma bonds and delocalized pi bonds (due to resonance).
- The C-C bond length in graphite is shorter than in diamond, approximately **141 picometers**.

3. **Understanding Naphthalene:**
- Naphthalene consists of two fused benzene rings, which also have sp² hybridization.
- The carbon atoms in naphthalene are involved in both sigma and pi bonding.
- The C-C bond length in naphthalene is approximately **137 picometers**, which is shorter than both diamond and graphite.

4. **Understanding Fullerene (C60):**
- Fullerene has a structure resembling a soccer ball, with carbon atoms arranged in a combination of pentagons and hexagons.
- The carbon atoms in fullerene are also sp² hybridized, contributing to both sigma and pi bonding.
- The C-C bond length in fullerene is around **146 picometers**, which is longer than naphthalene but shorter than diamond.

5. **Comparison of C-C Bond Lengths:**
- Diamond: 154 picometers
- Graphite: 141 picometers
- Naphthalene: 137 picometers
- Fullerene: 146 picometers

6. **Conclusion:**
- Among the given options, diamond has the maximum C-C bond length of **154 picometers**.

### Final Answer:
The C-C bond length is maximum in **diamond**.

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