What are isoelectronic species ? Give example to illustrate your answer.

Explanation

### Step-by-Step Solution:

**Step 1: Define Isoelectronic Species**
Isoelectronic species are atoms, ions, or molecules that have the same number of electrons. This means that despite possibly having different atomic numbers or charges, they share a common electron configuration.

**Step 2: Explain the Importance of Electron Count**
The electron count is crucial because it determines the chemical properties and reactivity of the species. Species with the same number of electrons often exhibit similar chemical behavior.

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