Textbook Exercise 1E.5

Moderators: Chem_Mod, Chem_Admin

Arezo Ahmadi 3J
Posts: 110
Joined: Wed Sep 30, 2020 9:41 pm
Been upvoted: 2 times

Textbook Exercise 1E.5

Postby Arezo Ahmadi 3J » Mon Nov 02, 2020 9:13 pm

Hi, I was looking at this problem and had a question about one of the statements: Which of the following statements are true for many-electron atoms? If false, explain why. (a) The effective nuclear charge Zeffe is independent of the number of electrons present in an atom. (b) Electrons in an s-orbital are more effective than those in other orbitals at shielding other electrons from the nuclear charge because an electron in an s -orbital can penetrate to the nucleus of the atom. (c) Electrons having l = 2 are better at shielding than electrons having l = 1. (d) Zeff e for an electron in a p-orbital is lower than for an electron in an s -orbital in the same shell.

My question is about part (c), as I do not understand why it is a false statement. I interpreted this statement in which electrons with l = 2 would have more electrons and thus be more expanded with a larger atomic radius, allowing those electrons to be better at shielding than electrons with l = 1 because those electrons would be more attracted to the nucleus due to the increase in protons. I was wondering if I could get an explanation about why this statement is true and the concepts behind electron shielding and when there is better or weaker electron shielding.

Thank you in advance!

Crystal Yu 1D
Posts: 129
Joined: Wed Sep 30, 2020 9:58 pm
Been upvoted: 12 times

Re: Textbook Exercise 1E.5

Postby Crystal Yu 1D » Mon Nov 02, 2020 9:16 pm

It is false because electrons with l=2 are located in the d orbitals. Electrons with l=1 are located in the p orbitals. For electrons with the same principle quantum number (n), the p orbitals would be located closer to the nucleus and thus be better at shielding because it has more opportunities to shield. I hope this makes sense! :)

Lily Kiamanesh 2G
Posts: 67
Joined: Wed Sep 30, 2020 10:09 pm

Re: Textbook Exercise 1E.5

Postby Lily Kiamanesh 2G » Tue Nov 03, 2020 12:10 am

Yes, electrons found closer to the nucleus are essentially "blocking" further electrons from fully experiencing the attraction from the positive charge of the nucleus. P-orbital electrons are closer to the nucleus than d-orbital electrons, so they block, or shield, more.

Jordi M 2I
Posts: 101
Joined: Wed Sep 30, 2020 9:40 pm

Re: Textbook Exercise 1E.5

Postby Jordi M 2I » Tue Nov 03, 2020 7:43 am

Yes the p orbital is better at shielding because it is closer to the nucleus than the d orbital. The p orbital shields the d and f orbitals on the same quantum level from the nucleus. If the question asked, the s orbital would be even better at shielding since it would shield p, d, and f orbital electrons.

Anna Yang 1A
Posts: 74
Joined: Wed Sep 30, 2020 9:43 pm

Re: Textbook Exercise 1E.5

Postby Anna Yang 1A » Tue Nov 03, 2020 1:13 pm

I believe closer proximity to the nucleus is linked to better shielding as the orbitals closer to the nucleus are able to shield the ones further away; thus the s-orbital shields the p, d, and f while the p shields the d and f and so on. Therefore, the d orbital would not be better at shielding than the p orbital, but it would be better at shielding than the f.


Return to “Quantum Numbers and The H-Atom”

Who is online

Users browsing this forum: No registered users and 1 guest