## Problem 3.65

$FC=V-(L+\frac{S}{2})$

Sydney Wu 2M
Posts: 50
Joined: Fri Jul 22, 2016 3:00 am

### Problem 3.65

How is possible for elements in Group 18 to form bonds (don't they already have a filled octet)?

Alexandra_Ivanova_1A
Posts: 26
Joined: Sat Jul 09, 2016 3:00 am

### Re: Problem 3.65

You're right-- Nobel gases (Group 18 elements) contain a full octet, so they don't usually (or at least, do not easily) form bonds with other elements. That being said, it is possible for them to bond, though that bond is often very weak.

Typically, elements n=3 and above don't follow the octet rule, and can have this expanded octet. Since Xenon (like in problem 3.65) is a fairly large atom, its hold on its electrons are weak, which allows for particularly electronegative atoms to form a covalent bond with it, allowing Xenon to bond with atoms like fluorine and oxygen like in the problem.