# Why is the Chlorine missing an electron in Chlorine Monoxide?

I was asked to draw the lewis-dot structure for ClO and I drew this:

   ..  ..
:Cl-  O.
..  ..


The correct answer is apparently this:

   .   ..
:Cl-  O:
..  ..


How would I know that? In the first example, all the formal charges are zero, but in the second, Oxygen has -1 and Chlorine has +1.

-
1. Lewis structures are models that help us predict things and understand things about ions and molecules. 2. In some problems there is no "right" answer, or be.tter to say, there are several answers, neither of which are really "right". I like your reasoning about formal charge, by the way. I would ask an additional question: What about CLO can we learn, predict, or understand better with one of those structures vs the other? – Brinn Belyea Jul 27 '14 at 20:26
intermolecular forces - would they be higher with the second due to the formal charge? – Jakob Weisblat Jul 27 '14 at 20:32
Maybe they would be weaker. The dipole moment of CO is .1D or so since C has a -1 and O a +1 formal charge. One might expect a C-O triple bond to be quite polar but it isn't. – Brinn Belyea Jul 27 '14 at 20:34