Drawing the Lewis Structure for AsF5

Viewing Notes:

  • There are a total of 40 valence electrons in AsF5.
  • Arsenic (As) is the least electronegative and goes at the center of the Lewis structure.
  • Arsenic (As) is in Period Four on the periodic table and can hold more than 8 valence electrons.



Transcript: This is the AsF5 Lewis structure. Arsenic has 5 valence electrons, Fluorine has 7, we have 5 Fluorines. So 5 plus 35: a total of 40 valence electrons for the AsF5 Lewis structure. Arsenic is the least electronegative, we'll put that at the center. Then we'll put 5 Fluorines around the Arsenic. We have a total of 40 valence electrons for the AsF5 Lewis structure.

We'll put chemical bonds between the Arsenic and the Fluorine atoms. There are 2 electrons in each chemical bond, so we've used 2, 4, 6, 8, 10. Then we'll go around the outside and complete the octets for the Fluorine. So we have 10, 12, 14, and 40. At this point, all the Fluorines have 8 valence electrons, so their octets are full, but the Arsenic has 2, 4, 6, 8, 10 valence electrons.

That's OK, though; Arsenic is in period 4 of the periodic table, so it can have more than 8 valence electrons. So for the AsF5 Lewis structure, we've used all 40 valence electrons. The octets are fulfilled on the Fluorine. The Arsenic has 10 valence electrons, but that's OK. If you check the formal charges, you'll see that the formal charges are 0, so that's good.

And this is the Lewis structure for AsF5. This is Dr. B., thanks for watching.