How can I draw the Lewis structure for CO?
Here are the steps that I follow when drawing a Lewis structure.
1. Decide which is the central atom in the structure. That will normally be the least electronegative atom (C).
2. Draw a skeleton structure in which the other atoms are single-bonded to the central atom: C-O.
3. Draw a trial structure by putting electron pairs around every atom until each gets an octet. In this editor, I will have to write it as :::C-Ö::
4. Count the valence electrons in your trial structure (14).
5. Now count the valence electrons you actually have available. 1 C + 1 O = 1×4 + 1×6 = 10. The trial structure has four extra electrons.
6. Draw a new trial structure, this time inserting one double bond for each extra pair of electrons : C≡O.
7. As before, add valence electrons to give each atom an octet :C≡O:
8. Calculate the formal charge on each atom :C⁻≡O⁺:
9. The “best” Lewis structure is usually one that has the fewest formal charges. We could draw a structure like :C=Ö: This has no formal charges, but the C atom does not have an octet.
Neither structure is "good", but the better structure is the first one.