Out of `Cr^(2+)` and `Cr^(3+)`, which one is stable in aqueous solution?

Explanation

To determine which of the chromium ions, \( \text{Cr}^{2+} \) or \( \text{Cr}^{3+} \), is more stable in aqueous solution, we can follow these steps:

### Step 1: Understand the Electronic Configuration
- The ground state electronic configuration of chromium (Cr) is \( [\text{Ar}] 3d^5 4s^1 \).
- When chromium loses two electrons to form \( \text{Cr}^{2+} \), its configuration becomes \( [\text{Ar}] 3d^4 \).
- When chromium loses three electrons to form \( \text{Cr}^{3+} \), its configuration becomes \( [\text{Ar}] 3d^3 \).

### Step 2: Compare the Size of the Ions
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