The total number of orbitals in fifth energy level should theoretically be

Options

A. 10
B. 25
C. 15
D. 18

Explanation

To determine the total number of orbitals in the fifth energy level, we can follow these steps:

### Step-by-step Solution:

1. **Identify the Principal Quantum Number (n)**:
- The principal quantum number (n) indicates the energy level of an electron in an atom. For the fifth energy level, n = 5.

2. **Use the Formula for Total Number of Orbitals**:
- The total number of orbitals in a given energy level can be calculated using the formula:
\[ \text{Total Orbitals} = n^2 \]

3. **Calculate the Total Number of Orbitals**:
- Substitute the value of n into the formula:
\[ \text{Total Orbitals} = 5^2 = 25 \]

4. **Conclusion**:
- Therefore, the total number of orbitals in the fifth energy level is 25.

### Final Answer:
The total number of orbitals in the fifth energy level is **25**.

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