Which of the molecules and polyatomic ions cannot be adequately described using a single lewis structure? hcn ch2cl2 o3 of2 co2-3 nh+4?

Only two on the choice is the answer, and it is O (3) and CO (3) ^2-The polyatomic ions and molecules that cannot be adequately described using a single lewis structure is 0 (3) and CO (3) ^2-

So, The answer in this question is C0 (3) ^2 - and 0 (3)