In group 1 (alkali metals), sodium is more reactive than lithium, or lithium is less reactive than sodium. Give reason.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Group 1 Elements:**
- Group 1 elements are known as alkali metals, which include lithium (Li), sodium (Na), potassium (K), rubidium (Rb), and cesium (Cs).

2. **Atomic Structure of Lithium and Sodium:**
- Lithium has the electronic configuration of 1s² 2s¹.
- Sodium has the electronic configuration of 1s² 2s² 2p⁶ 3s¹.
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