`C-C` bond length is maximum in

Options

A. `C_(60)`
B. graphite
C. `C_(70)`
D. diamond

Explanation

To determine which compound has the maximum C-C bond length, we need to analyze the hybridization and bonding characteristics of the given options.

### Step-by-Step Solution:

1. **Identify the Compounds**: The options provided are C60 (Buckminsterfullerene), graphite, diamond, and C70.

2. **Understand Hybridization**:
- **C60 (Buckminsterfullerene)**: It has sp2 hybridization. The structure consists of carbon atoms arranged in a spherical shape, with each carbon atom forming three sigma bonds and one pi bond.
- **Graphite**: It also has sp2 hybridization. In graphite, carbon atoms are arranged in layers, with each carbon forming three sigma bonds and one pi bond, resulting in a planar structure.
- **Diamond**: It has sp3 hybridization. In diamond, each carbon atom forms four sigma bonds with other carbon atoms, resulting in a tetrahedral structure.
- **C70**: Similar to C60, C70 has sp2 hybridization, with carbon atoms forming a structure that includes both sigma and pi bonds.

3. **Analyze Bond Lengths**:
- The bond length is influenced by the type of bond formed. Single bonds (sigma bonds) are longer than double bonds (which consist of one sigma and one pi bond).
- Since diamond has sp3 hybridization, it consists entirely of single C-C bonds. Therefore, it will have the longest bond length among the options provided.
- In contrast, C60, graphite, and C70 contain double bonds due to their sp2 hybridization, which results in shorter bond lengths compared to single bonds.

4. **Conclusion**: Since diamond has only single C-C bonds (sp3 hybridization), it has the maximum C-C bond length compared to C60, graphite, and C70, which have double bonds (sp2 hybridization).

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

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