The melting and boiling points of Zn, Cd and Hg are low. Why?

Explanation

To understand why the melting and boiling points of zinc (Zn), cadmium (Cd), and mercury (Hg) are low, we can analyze their electronic configurations and the nature of their metallic bonding.

### Step 1: Identify the Electronic Configurations
- **Zinc (Zn)**: Atomic number = 30
- Electronic configuration: \( \text{[Ar]} 3d^{10} 4s^2 \)

- **Cadmium (Cd)**: Atomic number = 48
- Electronic configuration: \( \text{[Kr]} 4d^{10} 5s^2 \)
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