Explain how VB theory differs from Lewis concept.

Explanation

### Step-by-Step Solution:

1. **Definition of Lewis Concept**:
- The Lewis concept, also known as Lewis dot structure, explains the formation of covalent bonds through the mutual sharing of electron pairs between atoms. It emphasizes the idea that atoms achieve stability by sharing electrons to fill their outer electron shells.

2. **Definition of Valence Bond (VB) Theory**:
- Valence Bond Theory, on the other hand, describes covalent bond formation as a result of the overlap of half-filled atomic orbitals. This theory focuses on the quantum mechanical nature of electrons and how their wave functions interact to form bonds.

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