Ionic potential is taken as charge/radius with radii $Li X^{+} = 76$ , $Na X^{+} = 102$ , $Mg X^{2 +} = 72$ , $Al X^{3 +} = 54$ and $Be X^{2 +} = 45 pm$ . Which cation has an ionic potential closest to that of $Be X^{2 +}$ , consistent with the diagonal relationship in the periodic table?

A $Na X^{+}$
B $Li X^{+}$
C $Mg X^{2 +}$
D $Al X^{3 +}$

Answer: D

Compute

ϕ

in charge per pm: Be 0.0444, Al 0.0556, Mg 0.0278, Li 0.0132, Na 0.0098. The nearest to Be is Al, with a difference of 0.0111, whereas Mg differs by 0.0167. This matches the Be-Al diagonal relationship.

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Ionic potential is taken as charge/radius with radii LiX+=76, NaX+=102, MgX2+=72, AlX3+=54 and BeX2+=45 pm. Which cation has an ionic potential closest to that of BeX2+, consistent with the diagonal relationship in the periodic table?

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Ionic potential is taken as charge/radius with radii $Li X^{+} = 76$ , $Na X^{+} = 102$ , $Mg X^{2 +} = 72$ , $Al X^{3 +} = 54$ and $Be X^{2 +} = 45 pm$ . Which cation has an ionic potential closest to that of $Be X^{2 +}$ , consistent with the diagonal relationship in the periodic table?