An electron will have highest energy in the set

Options

A. 3,2,1,1/2
B. 4,2,-1,1/2
C. 4,1,0,-1/2
D. 5,0,0,1/2

Explanation

To determine which electron has the highest energy in the given sets, we can use the n + l rule. This rule helps us compare the energy levels of different orbitals based on their principal quantum number (n) and azimuthal quantum number (l).

### Step-by-Step Solution:

1. **Identify the Quantum Numbers**:
- For each orbital, identify the principal quantum number (n) and azimuthal quantum number (l).
- The sets are:
- 3D: n = 3, l = 2
- 4P: n = 4, l = 1
- 4D: n = 4, l = 2
- 5S: n = 5, l = 0

2. **Calculate n + l for Each Orbital**:
- For 3D: n + l = 3 + 2 = 5
- For 4P: n + l = 4 + 1 = 5
- For 4D: n + l = 4 + 2 = 6
- For 5S: n + l = 5 + 0 = 5

3. **Compare n + l Values**:
- The calculated n + l values are:
- 3D: 5
- 4P: 5
- 4D: 6
- 5S: 5
- The highest n + l value is 6 for the 4D orbital.

4. **Determine the Highest Energy Level**:
- According to the n + l rule, the orbital with the highest n + l value has the highest energy.
- Since 4D has the highest n + l value (6), it has the highest energy among the given orbitals.

### Conclusion:
The electron will have the highest energy in the **4D** set.

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