Explain the structure of methane.Give an example of a molecule exhibiting `sp^(3)d^(2)` hybridisation. How is it possible for d-orbitals to mix with lower energy s and p orbitals?

Explanation

### Step-by-Step Solution

**1. Structure of Methane (CH₄):**
- The chemical formula of methane is CH₄.
- The valence electronic configuration of carbon is 2s² 2p².
- To form bonds, carbon can excite one of its 2s electrons to the 2p orbital, resulting in the configuration 2s¹ 2p³.
- This leads to the formation of four equivalent hybrid orbitals through sp³ hybridization.
- The sp³ hybridized orbitals arrange themselves in a tetrahedral geometry, with bond angles of approximately 109.5°.
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