What is the electronic configuration of `Cu^(2+)(Z=29)` of least position

Options

A. `[Ar]4s^(1)3d^(8)`
B. `[Ar]4s^(2)3d^(10)4p^(1)`
C. `[Ar]4s^(1)3d^(10)`
D. `[Ar]3d^(9)`

Explanation

To find the electronic configuration of \( \text{Cu}^{2+} \) (copper ion with a +2 charge), we need to follow these steps:

### Step 1: Determine the atomic number of copper
Copper (Cu) has an atomic number \( Z = 29 \). This means a neutral copper atom has 29 electrons.

### Step 2: Write the electronic configuration of neutral copper
The electronic configuration of a neutral copper atom is:
\[ \text{Cu}: [\text{Ar}] \, 3d^{10} \, 4s^1 \]
This configuration indicates that copper has a full \( 3d \) subshell and one electron in the \( 4s \) subshell.

### Step 3: Remove electrons to form \( \text{Cu}^{2+} \)
When copper loses two electrons to form \( \text{Cu}^{2+} \), the electrons are removed first from the \( 4s \) subshell and then from the \( 3d \) subshell. Therefore, we remove the one electron from \( 4s \) and one electron from \( 3d \).

1. Remove 1 electron from \( 4s \):
\[ 3d^{10} \, 4s^0 \]
2. Remove 1 electron from \( 3d \):
\[ 3d^9 \]

### Step 4: Write the final electronic configuration of \( \text{Cu}^{2+} \)
Thus, the electronic configuration of \( \text{Cu}^{2+} \) is:
\[ \text{Cu}^{2+}: [\text{Ar}] \, 3d^9 \]

### Final Answer:
The electronic configuration of \( \text{Cu}^{2+} \) is \( [\text{Ar}] \, 3d^9 \).

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