This method that the facets with the shortest ionization energies would certainly be in the bottom left-hand corner of the periodic table. The adjust in ionization energies is also bigger going down the periodic table (by adjust within a group) than going across the periodic table (by adjust within a period).

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So let"s start from the bottom of the regular table:#Pb# is the facet that is in the lowest period at 6 (and lowest group at 14) in the regular table; it"s the smallest ionization energy.

The period above (5) has actually two the the elements: Sn and Te. Well, because ionization power increases throughout a period, Sn will have actually a smaller ionization energy than Te.#Pb, Sn, Te#

Now, let"s go to the third period, wherein #S# and also #Cl# are. Since #S# is before #Cl,# #S# has a lower ionization energy than #Cl#.#Pb, Sn, Te, S, Cl#

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Ernest Z.
Nov 15, 2016

The order is #"Sn .


You have learned that ionization power increases from height to bottom and also from left to appropriate in the periodic Table.

You more than likely saw a chart something favor this.


Here"s the part of the periodic Table that consists of the facets in this question.

(Adapted from ZON PENA)

You would naturally predict the order to be


This is almost correct, but the exactly order is #"Sn , as displayed in the photo below.

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Why is this so?

The electron construction of #"Sn"# is #" 5s"^2 "4d"^10 "5p"^2#.

The electron construction of #"Pb"# is #" 6s"^2 "4f"^14 "5d"^10 "6p"^2#.

The #"4f"# electron in #"Pb"# are negative at shielding the outermost electrons.

Thus the outer electrons suffer a greater efficient nuclear charge, and it is more difficult to eliminate them.

Hence #"Pb"# has actually a greater ionization than #"Sn"#, and the exactly order is #"Sn .

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I hope that your instructor called you about this phenomenon prior to asking girlfriend to make a prediction.

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