Simple quantum question

[jammin06]

Sup everyone, i'm workin on the EK chemistry book right now, and i just came across the following question:

Compared to an electron with a principle quantum number of 1, an electron with a principal quantum number of 2 will have:

lower energy
higher energy
negative spin
positive spin

I think the answer is higher energy, but the book tells me that it's lower energy. Can someone explain this concept to me? Thanks a ton.

---

Members don't see this ad.

 

[duck2005]

nope. HIGHER energy. the lowest energy = ground state = lowest n. Furthermore, Energy of e- = -R/n^2. R is a constant. higher n = lower (R/n^2) = higher -R/n^2. Don't forget the negative in that equation. Plus, more generally, lower energies have aways been associated with lower n.

higher n does, though, mean lower ionization energy. energy of an e- in orbit is negative. energy of freed electron (after ionization) = 0. thus, the higher the n, the higher the energy (which means less negative), and the less energy necessary to raise this negative energy to a value of 0.

 

[Lion-O]

duck2005 nailed it: definitely higher energy.

 

[PhatGtDmB]

w/o a doubt HIGHER energy

 

[jammin06]

woo, so i've found my first error in the EK series....yay for me! maybe this an omen to tell me i wont COMPLETELY bomb the entire mcat

 

[lihini]

I agree HIGHER energy !

 

[fun8stuff]

nope. HIGHER energy. the lowest energy = ground state = lowest n. Furthermore, Energy of e- = -R/n^2. R is a constant. higher n = lower (R/n^2) = higher -R/n^2. Don't forget the negative in that equation. Plus, more generally, lower energies have aways been associated with lower n.

higher n does, though, mean lower ionization energy. energy of an e- in orbit is negative. energy of freed electron (after ionization) = 0. thus, the higher the n, the higher the energy (which means less negative), and the less energy necessary to raise this negative energy to a value of 0.

correct! .

 

[gdk]

you might want to check the errata on the ek website. that one might have already been noted, along with some others you haven't found yet

 

[jammin06]

yea, i posted it on their website, but no one has responded. They changed the format of website, so all the old posts are gone i think. It'll pick back up in the summer when everyone else is using the material though.

 

[tae1703]

i would say higher energy, unless i completely wasted my time and money going to my selected university

 

[ChemMN]

Everyone here is absolutely correct. An electron must gain energy in the form of a photon to be promoted to n=2. It doesn't radiate energy in this transition.