Here's the left side of the table, with those contours now in blue or brown. Note that the second blue contour for z/r = 2 goes through the middle of the rectangle for Ca2+. It has to, as dictated by the math we did a couple of slides back. The same logic dictates the position of all the contours.

        The part of the table as which we're looking shows cations from which all outer shell electrons have been removed. For example, Na+, Mg2+, Al3+, Si4+, P5+, and S6+ all have the same out-shell electron configuration, the same as that of neon. These ions are thus called "hard" cations, in that they more-or-less meet the expection of a hard sphere because their outer electron shell is full.

        We can continue these contours to the right . . .


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The first slide of this presentation
The last slide of this presentation
Railsback's main page about the Earth Scientist's Periodic Table of the Elements and Their Ions
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Railsback's main web page
UGA Geology Department web page

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