The electronic configuration of `Re^(3+)` is `(Xe)4f^(14)5d^(4)`, the number of unpaired electrons in this ion is ____________.

Explanation

To determine the number of unpaired electrons in the ion \( \text{Re}^{3+} \) with the electronic configuration \( (Xe) 4f^{14} 5d^{4} \), we can follow these steps:

### Step 1: Understand the Electronic Configuration
The electronic configuration given is \( (Xe) 4f^{14} 5d^{4} \). This indicates that:
- The \( 4f \) subshell is completely filled with 14 electrons.
- The \( 5d \) subshell has 4 electrons.

### Step 2: Analyze the \( 4f \) Subshell
...