The C—C bond length is maximum in :
(a)`C_(60)`
(b)diamond
(c)`C_(70)`
(d)All of these

Options

A. `C_(60)`
B. diamond
C. `C_(70)`
D. All of these

Explanation

To determine which of the given options has the maximum C—C bond length, we will analyze the bond lengths in each structure provided.

### Step 1: Understand the Structures
- **C₆₀ (Buckminsterfullerene)**: This molecule consists of 60 carbon atoms arranged in a spherical structure. It has a mix of single and double bonds due to its resonance structure.
- **Diamond**: In diamond, each carbon atom is bonded to four other carbon atoms in a tetrahedral structure, forming only single (sigma) bonds.
- **C₇₀**: Similar to C₆₀, C₇₀ is a fullerene with 70 carbon atoms. It also exhibits a mixture of single and double bond character.

### Step 2: Compare Bond Lengths
- **C₆₀**: The C—C bond length is approximately 1.4 Å.
- **C₇₀**: The bond length ranges from 1.37 Å to 1.46 Å.
- **Diamond**: The C—C bond length is about 1.54 Å.

### Step 3: Conclusion
From the bond lengths calculated:
- The C—C bond length in diamond (1.54 Å) is longer than that in C₆₀ (1.4 Å) and C₇₀ (1.37 Å to 1.46 Å).
- Therefore, the maximum C—C bond length is found in diamond.

### Final Answer
The C—C bond length is maximum in **(b) diamond**.

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