Valence Electrons in Radium (Ra)

Valence Electrons in Radium

Determine the number of valence electrons in Radium (Ra, Element 88)

Step 1: Look up the electronic configuration for Radium

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

[Rn] 7s²

Calculate Electronic Configuration for Radium

Step 2: Identify the outermost electrons using the electronic configuration

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

7s²

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

Radium (Ra) has 2 valence electron(s).