Valence Electrons in Lawrencium (Lr)

Valence Electrons in Lawrencium

Determine the number of valence electrons in Lawrencium (Lr, Element 103)

Step 1: Look up the electronic configuration for Lawrencium

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

[Rn] 5f¹⁴ 7s² 7p¹

Calculate Electronic Configuration for Lawrencium

Step 2: Identify the outermost electrons using the electronic configuration

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

5f¹⁴ 7s² 7p¹

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 = 7) are valence electrons.

Answer

Lawrencium (Lr) has 3 (2 + 1) valence electrons.