Graphite is soft because:

Explanation

**Step-by-Step Solution:**

1. **Understanding Graphite**: Graphite is an allotrope of carbon, which means it is one of the different structural forms of carbon.

2. **Layered Structure**: Graphite has a unique layered structure. Each layer is composed of carbon atoms arranged in a hexagonal lattice.

3. **Hybridization**: The carbon atoms in graphite are sp² hybridized. This means that each carbon atom forms three sigma bonds with its neighboring carbon atoms in the same layer.

4. **Planar Layers**: The layers in graphite are planar and can be visualized as 2D sheets. Each sheet is made up of hexagonal rings of carbon atoms.

5. **Weak Interlayer Forces**: Between these layers, there are weak van der Waals forces acting. These forces are much weaker than the covalent bonds within the layers.

6. **Mobility of Layers**: Due to the weak interlayer forces, the layers can slide over one another easily. This property allows graphite to be soft and lubricating.

7. **Conclusion**: Therefore, graphite is soft because of its layered structure, the weak forces between the layers, and the ability of these layers to slide over each other.

**Final Answer**: Graphite is soft because it has a layered structure with weak interlayer forces that allow the layers to slide over one another easily.

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