Question #27e4d
1 Answer
This is actually hard to do completely without actual data.
INITIAL GUESS
My initial ordering would be based on charge (smallest to largest):
#"Al"^(3+)# #"Mg"^(2+)# #"Na"^(+)# #"Ne"# #"F"^(-)# #"O"^(2-)# #"O"^(3-)#
since a larger positive charge gives a larger effective nuclear charge relative to an element on the same period with a smaller positive charge, and thus a smaller ionic radius.
But we are looking way across the periodic table, and the period trend and group trend overlap.
PERIOD/GROUP TREND CONFLICTS
Recall that the atomic radius resets to be bigger due to the addition of a new quantum level
How much smaller does
The actual radii are:
#"53 pm"# (ionic radius)#"72 pm"# (ionic radius)#"102 pm"# (ionic radius)#"69 pm"# (covalent radius)#"133 pm"# (ionic radius)#"140 pm"# (ionic radius)#>"140 pm"# (ionic radius)
respectively, for the species listed at the top.
So I would have misplaced
(And I could also be wrong if the atomic radii I referenced were poorly calculated or poorly determined as well, because
The "real" order, at least based on the data I referenced, would be (from smallest to largest):
#"Al"^(3+)# ,#r_"ionic" = "53 pm"# #"Ne"# ,#r_"covalent" = "69 pm"# #"Mg"^(2+)# ,#r_"ionic" = "72 pm"# #"Na"^(+)# ,#r_"ionic" = "102 pm"# #"F"^(-)# ,#r_"ionic" = "133 pm"# #"O"^(2-)# ,#r_"ionic" = "140 pm"# #"O"^(3-)# ,#r_"ionic" > "140 pm"#
