Question

Which one of the following fluorides does not exist?

Options

• HeF₄

• XeF₄

• CF₄

• SF₆

Answer 1

HeF₄

Explanation:

Helium is a noble gas with a completely filled 1s² shell and very high ionisation energy, making it chemically inert. It does not form any stable compounds with fluorine. Therefore, HeF₄ does not exist.
On the other hand, XeF₄, CF₄, and SF₆ are well-known and stable fluorides.