Valence Electrons in Promethium (Pm)
Calculate the number of valence electrons in Promethium using its electron configuration step by step.
Valence Electrons in Promethium
Determine the number of valence electrons in Promethium (Pm, Element 61)
Step 1: Look up the electronic configuration for Promethium
The abbreviated (condensed) ground electronic configuration for Promethium is:
[Xe] 4f5 6s2
Calculate Electronic Configuration for Promethium
Step 2: Identify the outermost electrons using the electronic configuration
Electrons in atomic orbitals outside the [Xe] core are the outermost electrons:
4f5 6s2
Step 3: Use the principle quantum number to identify the valence electrons
Extract the principle quantum number, n, and number of electrons from the electron configuration:
| Electron Configuration | n | Orbital | Number of Electrons |
|---|---|---|---|
| 4f5 | 4 | f | 5 |
| 6s2 | 6 | s | 2 |
The outermost electrons with the largest principal quantum number (in this case, n = 6) are valence electrons.
Answer
Promethium (Pm) has 2 valence electron(s).
