## 3.49 part c

georgia_perris4G
Posts: 19
Joined: Wed Sep 21, 2016 2:57 pm

### 3.49 part c

Draw the Lewis structure and determine the formal charge on each atom in (c) CO

why is there a triple bond between the two elements and not a double bond? The triple bond gives the carbon a 1+ formal charge and the oxygen a -1 formal charge but I thought the purpose of the formal charge was to get each of the elements' formal charge to equal zero? Please help I am confused

Sally_Tu_1H
Posts: 22
Joined: Fri Jul 22, 2016 3:00 am
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### Re: 3.49 part c

Lewis structures must satisfy the total number of valence electrons.
And so, if you count up the valence electrons of both atoms, you would get 10 electrons. Therefore, with a triple bond, you can satisfy this total number of valence electrons. Triple bond (6 electrons) and a lone pair on each atom (2x2=4 valence electrons). However, with a double bond, you would get a total of 12 valence electrons. This part must be achieved before determining the formal charge.