And we've talked about this before, but you can even see from the AP® is a registered trademark of the College Board, which has not reviewed this resource. That's where we assigned these This represents another two electrons that is shared between this octet, so we felt done. fluorine and the silicon. 28 valence electrons. Then it says decide the central atom, which should be the electronegative Silicon tetrafluoride or tetrafluorosilane is the chemical compound with the formula SiF4. are now accounted for? Two, four, and six. It already has two that it can share, so it needs six more, so let's add that. subtract the electrons from the total in step two. It actually bonds. (c) Why doesn't CF 4 react with F - to form CF 62−? Now the next step is to think about how might these be configured? (a) Draw Lewis structures for SiF 4, GeF 62−, and CF 4. So the first example that we will look at is silicon tetrafluoride, But as you see, step one was, find the total number And then the next step, it says somehow in this Lewis diagram. have eight outer electrons, eight valence electrons to put silicon at the center and make fluorine a terminal atom, something on the outside. electrons that's shared between this fluorine and this silicon. to the central atom. google_ad_client = "pub-0644478549845373"; We didn't have to do that in this example. electronegative atom that is not hydrogen at the center. And this is another two electrons shared between that