The number of unpaired electrons in `Zn^(2+)` is

Explanation

To determine the number of unpaired electrons in the \( \text{Zn}^{2+} \) ion, we can follow these steps:

### Step 1: Determine the Atomic Number of Zinc
Zinc (Zn) has an atomic number of 30. This means that a neutral zinc atom has 30 electrons.

### Step 2: Write the Electronic Configuration of Neutral Zinc
The electronic configuration of neutral zinc can be written as:
\[ \text{Zn}: [\text{Ar}] \, 3d^{10} \, 4s^2 \]
Here, [Ar] represents the electron configuration of Argon, which accounts for the first 18 electrons.

### Step 3: Adjust for the \( \text{Zn}^{2+} \) Ion
To find the electronic configuration of \( \text{Zn}^{2+} \), we need to remove 2 electrons from the neutral zinc configuration. Electrons are removed first from the outermost shell, which is the 4s orbital.

Thus, the electronic configuration for \( \text{Zn}^{2+} \) becomes:
\[ \text{Zn}^{2+}: [\text{Ar}] \, 3d^{10} \]
The 4s electrons are removed, leaving us with the 3d electrons.

### Step 4: Analyze the 3d Orbital
The \( 3d \) subshell can hold a maximum of 10 electrons. In the case of \( \text{Zn}^{2+} \), the \( 3d \) subshell is fully filled with 10 electrons:
\[ 3d^{10} \]
Since all 10 electrons in the \( 3d \) subshell are paired, there are no unpaired electrons.

### Conclusion
The number of unpaired electrons in \( \text{Zn}^{2+} \) is:
\[ \text{Number of unpaired electrons} = 0 \]

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