What is allotropy?

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Allotropy**: Allotropy refers to the existence of an element in two or more different forms in the same physical state.

2. **Example of Allotropy**: A common example of allotropy is carbon, which has several allotropes including:
- **Graphite**: A form of carbon where atoms are arranged in layers, allowing them to slide over each other, making it slippery.
- **Diamond**: Another form of carbon where each atom is bonded to four other atoms in a three-dimensional structure, making it extremely hard.
- **Buckminsterfullerene (C60)**: A molecular form of carbon that resembles a soccer ball, consisting of 60 carbon atoms arranged in a hollow sphere.

3. **Characteristics of Allotropes**: Allotropes of an element can have different physical and chemical properties despite being composed of the same type of atoms.

4. **Conclusion**: The phenomenon of an element existing in multiple forms is termed "allotropy," and the different forms are referred to as "allotropes."

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