Valence electrons [ENDORSED]

[Emma Li 2C]

For elements with 3d and 4s electrons, should the valence electrons include the 3d block as well as the 4s block?
Thank you!

[Rebecca Cheung 1E]

Yes, those are the outermost electrons (valence e-).

[Madeline Musselman 3H]

The 4s block is where the outermost electrons are located (valence electrons) rather than the 3d block. When you write out the electron configuration for Magnesium, for example, the electron configuration is [Arg] 4s^2 3d^5 where the valence electrons are located in 4s with 2 valence electrons. I hope this little outline helps.

[Sonja Kobayashi 1H]

Hello everyone!
Yes, all of those electrons are valence electrons so it is important to know that all of those electrons play a role in how the element forms chemical bonds with other elements!

[Clarissa Molina 1D]

For question 2.37b, why are electrons in an s-orbital more effective than those in other orbitals at shielding electrons from nuclear charge?

[Kaelie Blanes-Ronda 2L]

The 2s electrons can be taken from the atom which would leave the other electrons from different orbitals behind, therefore shielding them from other electronegative atoms.

[Caroline Crotty 1D]

When we fill in the electron orbitals, we have to follow Aufbau's method. This means all levels must be present, including the 3d and 4s levels.

[Amir Akhavan 1E]

Yes those are considered to be the valance electrons.