Compare the stability of +2 oxidation state for the elements of the first transition series.

Explanation

To compare the stability of the +2 oxidation state for the elements of the first transition series, we will analyze the electronic configurations and the factors affecting the stability of this oxidation state across the series. The first transition series includes the elements Scandium (Sc), Titanium (Ti), Vanadium (V), Chromium (Cr), Manganese (Mn), Iron (Fe), Cobalt (Co), Nickel (Ni), Copper (Cu), and Zinc (Zn).

### Step-by-Step Solution:

1. **Identify the Elements of the First Transition Series**:
- The first transition series consists of the elements Sc (21), Ti (22), V (23), Cr (24), Mn (25), Fe (26), Co (27), Ni (28), Cu (29), and Zn (30).

2. **Write the Electronic Configurations**:
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