Only the unpaired electrons present in the outermost shell of an atom are called valence electrons.

Explanation

To determine whether the statement "Only the unpaired electrons present in the outermost shell of an atom are called valence electrons" is true or false, we can analyze the concept of valence electrons step by step.

### Step-by-Step Solution:

1. **Understanding Valence Electrons**:
- Valence electrons are defined as the electrons present in the outermost shell (also known as the valence shell) of an atom.

2. **Identifying the Outermost Shell**:
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