To determine which of the given elements has the maximum number of unpaired electrons, we will analyze the electronic configurations of each element step by step.
### Step 1: Identify the Elements and Their Atomic Numbers
The elements provided are:
1. Manganese (Mn) - Atomic Number 25
2. Titanium (Ti) - Atomic Number 22
3. Vanadium (V) - Atomic Number 23
4. Aluminum (Al) - Atomic Number 13
### Step 2: Write the Electronic Configurations
Next, we write the electronic configurations for each element.
1. **Manganese (Mn)**:
- Atomic Number: 25
- Electronic Configuration: \( \text{[Ar]} \, 3d^5 \, 4s^2 \)
2. **Titanium (Ti)**:
- Atomic Number: 22
- Electronic Configuration: \( \text{[Ar]} \, 3d^2 \, 4s^2 \)
3. **Vanadium (V)**:
- Atomic Number: 23
- Electronic Configuration: \( \text{[Ar]} \, 3d^3 \, 4s^2 \)
4. **Aluminum (Al)**:
- Atomic Number: 13
- Electronic Configuration: \( \text{[Ne]} \, 3s^2 \, 3p^1 \)
### Step 3: Determine the Number of Unpaired Electrons
Now, we will determine the number of unpaired electrons for each element based on their electronic configurations.
1. **Manganese (Mn)**:
- Configuration: \( 3d^5 \, 4s^2 \)
- In the 3d subshell, there are 5 electrons. According to Hund's rule, each of the 5 d orbitals will have one unpaired electron before any pairing occurs. The 4s subshell has 2 paired electrons.
- **Total Unpaired Electrons = 5 (from 3d)**
2. **Titanium (Ti)**:
- Configuration: \( 3d^2 \, 4s^2 \)
- In the 3d subshell, there are 2 electrons. Both will occupy separate orbitals, leading to 2 unpaired electrons. The 4s subshell has 2 paired electrons.
- **Total Unpaired Electrons = 2 (from 3d)**
3. **Vanadium (V)**:
- Configuration: \( 3d^3 \, 4s^2 \)
- In the 3d subshell, there are 3 electrons. Each will occupy separate orbitals, leading to 3 unpaired electrons. The 4s subshell has 2 paired electrons.
- **Total Unpaired Electrons = 3 (from 3d)**
4. **Aluminum (Al)**:
- Configuration: \( 3s^2 \, 3p^1 \)
- In the 3p subshell, there is 1 electron, which is unpaired. The 3s subshell has 2 paired electrons.
- **Total Unpaired Electrons = 1 (from 3p)**
### Step 4: Compare the Number of Unpaired Electrons
Now, we summarize the number of unpaired electrons for each element:
- Manganese (Mn): 5 unpaired electrons
- Titanium (Ti): 2 unpaired electrons
- Vanadium (V): 3 unpaired electrons
- Aluminum (Al): 1 unpaired electron
### Conclusion
The element with the maximum number of unpaired electrons is **Manganese (Mn)** with **5 unpaired electrons**.
