Why is `MgCl_(2)` molecule linear whereas the molecules of `SnCl_(2)` chloride has angulare shape ?

Explanation

To understand why the `MgCl₂` molecule is linear while the `SnCl₂` molecule has an angular shape, we need to analyze the molecular geometry of both compounds based on their valence electrons and the presence of lone pairs.

### Step-by-Step Solution:

1. **Identify the Valence Electrons:**
- Magnesium (Mg) is in Group 2 of the periodic table and has 2 valence electrons.
- Tin (Sn) is in Group 14 and has 4 valence electrons.

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