Drawing the Lewis Structure for IF2-

Viewing Notes:

  • In the IF2- Lewis structure Iodine (I) is the least electronegative atom and goes in the center of the Lewis structure.
  • The IF2- Lewis structure you'll need to put more than eight valence electrons on the Iodine atome.
  • In the Lewis structure for IF2- there are a total of 22 valence electrons.

Transcript: 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.