### Delta

Posted:

**Fri Oct 18, 2019 10:19 am**Can someone explain why delta is negative when the change in an electron goes from N=1 to N=3?

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=27&t=47916

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Posted: **Fri Oct 18, 2019 10:19 am**

Can someone explain why delta is negative when the change in an electron goes from N=1 to N=3?

Posted: **Fri Oct 18, 2019 10:22 am**

I think when an e- goes from n=3 to n=1 the change in energy is negative because its releasing energy (going from a higher energy state to a lower one, and the change in energy is measured as En(final) - En(initial)). Going from n=1 to n=3 should be a positive change in energy since you have to absorb energy to move up the energy levels.

Posted: **Fri Oct 18, 2019 11:23 am**

Whenever a electron goes from a higher energy state to a lower one the electron's energy has decreased and the energy is released as electromagnetic radiation, so we use the negative sign to describe the change in energy. This can be calculated through E=-hR/n^2 and delta E= Ef-Ei. Hope this helps!!

Posted: **Fri Oct 18, 2019 1:27 pm**

the change in energy should not be negative when n goes from 1 to 3 because electrons need to absorb energy in order to do that, making the sign in front of delta always a positive one.