From the electronic configurations Li (2, 1), Na (2, 8, 1) and K (2, 8, 8, 1), answer the following questions:
Which one is the most reactive?

Explanation

To determine which element among Lithium (Li), Sodium (Na), and Potassium (K) is the most reactive, we can follow these steps:

### Step 1: Understand the Electronic Configurations
- Lithium (Li) has the electronic configuration: 1s² 2s¹
- Sodium (Na) has the electronic configuration: 1s² 2s² 2p⁶ 3s¹
- Potassium (K) has the electronic configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹

### Step 2: Identify the Group and Period
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