Which is likely to form a molecule that doesnt obey the octet rule: B, C, O, P, or Be?

Answer 1

P phosphorus

anythin in the first 2 periods wont.
elements in the 3rd period n below can due to have a d subshell of electrons, sulfur is another common example.

Answer 2

B forms compounds (e.g. BF3) that are usually written with just 6 electrons on B.

But P forms compounds such as PF5, which give a Lewis structure with 10 electrons on P.

So (unless you are supposed to know fancy stuff about double bond contributions in BF3) the answer is that B and P both do this.

Answer 3

boron

Answer 4

phosphorus