Valence Electrons in Thulium (Tm)

Valence Electrons in Thulium

Determine the number of valence electrons in Thulium (Tm, Element 69)

Step 1: Look up the electronic configuration for Thulium

The abbreviated (condensed) ground electronic configuration for Thulium is:

[Xe] 4f¹³ 6s²

Calculate Electronic Configuration for Thulium

Step 2: Identify the outermost electrons using the electronic configuration

Electrons in atomic orbitals outside the [Xe] core are the outermost electrons:

4f¹³ 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:

The outermost electrons with the largest principal quantum number (in this case, n = 6) are valence electrons.

Answer

Thulium (Tm) has 2 valence electron(s).