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Ionization Energy

Posted: Sun Oct 16, 2016 8:45 pm
by Alejandra_Vasquez_1B
I am having difficulty understanding how to determine the ionization energy level of an atom. Is there any way to figure out which atom has a lower ionization level for a lewis structure?

Re: Ionization Energy

Posted: Mon Oct 17, 2016 8:03 am
by Kevin Tam 1J
As for determining the exact ionization energy level of each element, I don't know if such a task is within or beyond the scope of this course.

These are the general trends for ionization energy.

As you go across a period, the ionization energy generally increases. The exceptions for this periodic trend include Be and B, and N and O.
As for the Be and B exception, this can be explained by the fact that removing an e- from B is easier than removing an e- from Be because the e- from B is entering a new subshell, the p-subshell, thus making this e- easier to remove than the e- that completes the s-subshell of Be.
As for the N and O exception, this can be explained by the fact that removing an e- from O is easier than removing an e- from N because the e- from O experiences electron-electron repulsion, thus making this e- easier to remove than an e- from N that experiences no repulsion.

As you go down a group, the ionization energy generally decreases. This is because you are adding a new shell as you go down a group. This new shell of electrons, since it is farther away from the nucleus, will have electrons that are easier to remove and thus require less energy to remove.