energy level of electrons

[bayan]

i searched the web for the energy level of electrons and i found out two figures. in one it said the the higher energy level electrons are further away from the nuclie and in the other one it said the higher energy level electrons are closer to nucli.

i wanted to know which one is the right answer.

for example does the electron in Na move to third shell and then back to second to make a light wave or does it go to the first shell and then back to second shell to make a light wave?

i would apriciate your comants

[Chen]

The mechanical energy of the electron doesn't change, does it? It's its potential and kinetic energies that change. The closer the electron is to the nuclei, the more potential energy it has and the less kinetic energy it has (and vice versa).

[cookiemonster]

Higher shells have more energy. That's how a photon can pop out when an electron falls from a higher shell to a lower one. The photon's energy has to come from somewhere.

As for the kinetic energies of electrons, that's a tricky subject...

cookiemonster

[Chen]

The shells that are closer to the nuclei, are they called higher shells or lower shells?

[cookiemonster]

I've never seen shells closer to the nucleus referred to as higher shells. How's n = 1 higher than n = 2?

cookiemonster

[jcsd]

Well it's not really accurate to talk about electrons being, closer/further away from the nucleus, but if we ignore this and stick to the solar system model of the atom I think what has you confused is the difference between ionization energy and energy levels. The closer a bound electron is to a nucleus the lower it's energy level, but the higher it's ionization energy is.