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Garlic Bread Review 10d

Posted: Sun Nov 04, 2018 9:04 pm
by 705170809
10d) Rank the following in order of increasing ionization energies: C N O F
Why is the order C<O<N<F? If the period trend for ionization energy is decreasing as we go down the periods on the periodic table, and increasing as the we go from left to right on the period, shouldn't it be C<N<O<F?

Re: Garlic Bread Review 10d

Posted: Sun Nov 04, 2018 9:12 pm
by kateminden
This case is actually an exception to the rule. In the review session, we went over how because nitrogen has 1/2 shell stability (with 3 electrons in the 2p subshell), it actually has a higher ionization energy than oxygen, despite the periodic table trend. Similarly, carbon has a higher electron affinity than nitrogen because of N's 1/2 shell stability. I think these are the two exceptions we're expected to know for the test.

Re: Garlic Bread Review 10d

Posted: Sun Nov 04, 2018 10:08 pm
by Niveda_B_3I
also, this half shell stability extends to things like Boron and why it doesn't need a full octet.

Re: Garlic Bread Review 10d

Posted: Sun Nov 04, 2018 11:29 pm
by Nell Mitchell 1E
Ionization energy is the energy needed to remove an electron. Nitrogen has a half filled shell which is more stable than a having a half filled shell and then another electron (like oxygen). Because of this stability it takes more energy to remove an electron from nitrogen than it does to remove one from oxygen, even though nitrogen is to the left of oxygen on the periodic table.