Find the outermost electrons in f orbital in element Np

Answer

To find the outermost electrons in the f orbital for the element Neptunium (Np), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Element**:
- Neptunium (Np) is an actinide with the atomic number 93.

2. **Determine the Electron Configuration**:
- To find the electron configuration, we can use the noble gas shorthand notation. The closest noble gas before Neptunium is Radon (Rn), which has an atomic number of 86.

3. **Write the Electron Configuration**:
- The electron configuration of Neptunium can be written as:
\[ [Rn] \, 5f^4 \, 6d^1 \, 7s^2 \]
- Here, the notation indicates that Neptunium has 4 electrons in the 5f orbital, 1 electron in the 6d orbital, and 2 electrons in the 7s orbital.

4. **Identify the Outermost f Electrons**:
- The outermost f orbital for Neptunium is the 5f orbital. From the electron configuration, we see that there are 4 electrons in the 5f orbital.

5. **Conclusion**:
- Therefore, the number of outermost electrons in the f orbital for Neptunium (Np) is **4**.

### Final Answer:
The outermost electrons in the f orbital in element Neptunium (Np) is **4**.

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