Page 1 of 1

Lower in Energy?

Posted: Sun Nov 05, 2017 5:11 pm
by RuchaDeshpande1L
When asked which orbital is lowest in energy, should we look at the principal quantum number (n) or angular momentum quantum number (l, determines whether s,p,d,etc subshell)? As in, would 3d be lower in energy, or would 4s be lower?

Re: Lower in Energy?

Posted: Sun Nov 05, 2017 5:19 pm
by Vincent Kim 2I
Typically we look at the principal quantum number to determine which orbital is lower in energy, but in the case of 3d and 4s, 4s is lower.

Re: Lower in Energy?

Posted: Sun Nov 05, 2017 6:14 pm
by Annalise Eder 2L
The quantum number n gives the energy level while the angular momentum quantum number tells you the subshell of the electron. So use n as l does not give you information about the energy level. For potassium and Calcium 4s has lower energy than 3d which may seem counterintuitive, but for Scandium through Zinc 3d is slightly lower in energy than 4s.

Re: Lower in Energy?

Posted: Sun Nov 05, 2017 8:52 pm
by Bansi Amin 1D
3d is higher in energy than 4s when the d orbital is empty. When 3d has an electron in it, 3d becomes lower in energy than 4s.

Re: Lower in Energy?

Posted: Wed Nov 15, 2017 12:59 am
by Rithik Kumar 3E
If we consider an elementary model of atoms and their quantum structure I believe we should use the principal quantum value or the "n value" to determine the relative levels of energy. However, it should be taken into consideration that, for example, the 3d orbital is higher in energy than the 4s orbital until it gains an electron.

Re: Lower in Energy?

Posted: Mon Apr 23, 2018 12:44 am
by Kailie_Giebink_1E
in chemistry is everything is relative to the problem? or is there a hard rule to follow here?

Re: Lower in Energy?  [ENDORSED]

Posted: Mon Apr 23, 2018 3:45 pm
by Chem_Mod
Bansi's answer is what you would consider a "hard rule" and is correct. :)