Drawing the Lewis Structure for IF3

Viewing Notes:

  • In the IF3 Lewis structure Iodine (I) is the least electronegative atom and goes in the center of the Lewis structure.
  • The IF3 Lewis structure you'll need to put more than eight valence electrons on the Iodine atom.
  • In the Lewis structure for IF3 there are a total of 28 valence electrons.

Transcript: This is the IF3 Lewis structure. Iodine has 7 valence electrons. Fluorine, 7 as well, but we have three Fluorines for a total of 28 valence electrons. Iodine is the least electronegative, so we'll put it in the center, and then we'll put our Fluorines on the outside. We'll put a chemical bond between the Iodine and the Fluorines, like this. So we've used 2, 4, 6 valence electrons. Form the octets on the Fluorines. So we have 6, 8, 10, 24, so we've used 24, but we have 28.

We have four additional valence electrons. The Fluorines all have octets, but the Iodine doesn't have an octet. We also know that Iodine is in period 5, so it can even hold more than eight valence electrons. So let's put our four valence electrons, let's put two right here and two right here; and we've used all of our valence electrons. So this is the Lewis structure for IF3-. If you check your formal charges, you'll find they're all zero. We've used all the electrons that we started with. Everything has octets, and Iodine has more than an octet but that's OK, since it's in period 5.

This is Dr. B., and thanks for watching.