Explain why the elements of the same group exhibit the same chemical behaviour.

Explanation

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

1. **Definition of Groups in the Periodic Table**:
- The periodic table is organized into vertical columns known as groups. Each group contains elements that share similar properties.

2. **Valence Electrons**:
- Elements in the same group have the same number of valence electrons. Valence electrons are the electrons located in the outermost shell of an atom and are crucial in determining how an element reacts chemically.

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