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This is the IF2- Lewis structure. Iodine, 7 valence electrons. Fluorine also has 7,
but we have two Fluorines; and then we have an extra valence electron from that negative
sign for a total of 22 valence electrons. Iodine's the least electronegative. Let's
put that in the center and then Fluorines can go on the outside. We'll put two valence
electrons between the atoms to form chemical bonds, that's 4; and then around the outside,
6, and 16. So we've used 16. We have a total of 22 valence electrons, so we have six valence
electrons and we're going to have to put them all on the central Iodine here. We'll put
a pair here, a pair here, and then a pair down here. Now the Fluorines each have eight
valence electrons. So the Fluorines have octets. But the central Iodine, it has 2, 4, 6, 8,
10 valence electrons. That's OK because Iodine is in period 5 of the periodic table. It can
hold more than eight valence electrons. If you check the formal charges, you'll see that
the Iodine has a negative one formal charge. The formal charge on the Fluorines is zero.
That makes sense because this is a negative one charge for the entire molecule. So to
show that IF2- is an ion, we do need to put brackets around the Lewis structure like that,
and then put a negative sign out here to show that it's a negative ion. So that's the Lewis
structure for IF2-. This is Dr. B., and thanks for watching.