Drawing the Lewis Structure for ClF5

Viewing Notes:

  • For ClF5 Cl goes in the center since it is the least electronegative.
  • You will need to place the remaining two valence electrons on the central Cl after filling the octets of the Fluorine atoms.
  • For the ClF5 Lewis structure there are a total of 42 valence electrons available.

Transcript: This is Dr. B. Let's do the ClF5 Lewis structure. Chlorine has 7 valence electrons. Fluorine, in the same group, has 7, but we have five Fluorines. Seven plus 35: 42 total valence electrons. We'll put the Chlorine at the center and the Fluorines around it, just like this here. Form chemical bonds between the Chlorine and each Fluorine. Each bond is two valence electrons. Two, 4, 6, 8, 10; we've used ten valence electrons. Let's put electrons around the outside atoms, the Fluorines. So we have 10, 12, 14, and 40, and we have two left over. What we'll do with those two is, we'll place those right here on the central Chlorine, just like that.

At this point, we should check the formal charges to see if this is the best structure for ClF5. For Chlorine, we look on the periodic table and it has 7 valence electrons. And here in our Lewis structure, two of those are nonbonding, where 2, 4, 6, 8, 10 are bonding. We'll divide that by two. Seven minus 2 minus 5; zero is the formal charge for Chlorine. For Fluorine, they're all symmetrical, so we only need to do one. On the periodic table, it's in group 7 or 17, so it has 7 valence electrons. We have these right here as our nonbonding; six of them. And our bond right here, we have 2, which we'll divide by two. Seven minus 6 minus 1 is zero. So our formal charges are zero for each atom in ClF5. We've used all the 42 valence electrons we started with.

So that makes this the best structure for ClF5. This is Dr. B., thanks for watching.