shielding effect of s and p-orbitals

[Sue Xu 2K]

In the homework question 2.37 it says "an electron in an s-orbital can penetrate to the nucleus of the atom". What does it mean by "penetrate"?

[Amanda Hagen 1L]

S-electrons can "penetrate" the nucleus (be found at the nucleus) because it has a nonzero probability at the nucleus. Therefore the s-oribtal has a spherical shape encompassing the nucleus, while the higher orbitals (p,d,f) have nodal planes (zero probability of being found) at the nucleus.

[Sophie Krylova 2J]

How does the ability to "penetrate" the nucleus account for higher Zeff?

[Hyein Cha 2I]

How does the ability to "penetrate" the nucleus account for higher Zeff?

Ability to penetrate means that the electron can be closer to the nucleus, thus the net positive charge experienced by the electron will be stronger than the net positive charge experienced by the electron that's farrr away from the nucleus, making Zeff higher.

[Jessica Schirmer 1J]

An e- in a s-orbital can penetrate the nucleus because according to Schrodinger's wave equation, the 3D shape/probability of the s-orbital has no nodes (probability never reaches zero).