Which of the folllowing statements is incorrect regarding diamond?

Options

A. In diamond, each carbon atom is covalently bonded to four other carbon atoms
B. In graphite , each carbon atom is covalently bonded to three other carbon atoms in the same plane
C. The C-C bond length in graphite is intermediate between single and double bond distance
D. Diamond is a layered structure, the two layers joined by van der Wall's forces .

Explanation

To determine which statement is incorrect regarding diamond, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement 1: In diamond, each carbon atom is covalently bonded to four other carbon atoms.**
- In diamond, the structure is tetrahedral, where each carbon atom forms four covalent bonds with four other carbon atoms. This is a characteristic feature of diamond. Therefore, this statement is **correct**.

2. **Statement 2: In graphite, each carbon atom is covalently bonded to three other carbon atoms in the same plane.**
- Graphite has a planar structure where each carbon atom is bonded to three other carbon atoms in the same layer. This bonding arrangement gives rise to its layered structure. Thus, this statement is also **correct**.

3. **Statement 3: The carbon-carbon bond length in graphite is intermediate between single and double bond distance.**
- In graphite, the carbon-carbon bonds are indeed of a hybrid nature, which results in bond lengths that are intermediate between typical single and double bonds. Hence, this statement is **correct**.

4. **Statement 4: Diamond is a layered structure. The two layers are joined by Van der Waals forces.**
- This statement is incorrect. Diamond does not have a layered structure; instead, it has a three-dimensional tetrahedral lattice structure. The bonds in diamond are strong covalent bonds, not layers held together by Van der Waals forces. Therefore, this statement is **incorrect**.

### Conclusion:
The incorrect statement regarding diamond is: **"Diamond is a layered structure. The two layers are joined by Van der Waals forces."**

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