Lewis Structure

CO Lewis Structure

Carbon monoxide

CO is commonly drawn with a C-O triple bond, one lone pair on each atom, C with -1 formal charge, and O with +1 formal charge.

Use the diagram and steps below to check the carbon monoxide Lewis structure, CO Lewis dot structure, valence electrons, formal charges, and molecular shape.

CO

Carbon monoxide

10 e-
C - O +
Valence electrons10
Central atomNone
GeometryLinear
Bond angleNot applicable
PolarityPolar
Electron geometryNot applicable (diatomic)

Molecular Geometry

Molecular geometry Linear
Bond angle Not applicable
Polarity Polar
Valence electrons 10
Bond pairs / lone pairs per atom 3 / 1 each

How to Draw CO: Step-by-Step

1

Parse the molecular formula

CO -> C, O

The molecule contains one carbon atom and one oxygen atom.

2

Count total valence electrons

4 + 6 = 10

Carbon contributes 4 electrons and oxygen contributes 6.

3

Draw the skeleton

C-O

Start by connecting carbon and oxygen with a single bond.

4

Form a triple bond

C triple bond O

Three shared electron pairs give both atoms an octet.

5

Check formal charges

C = -1; O = +1

One lone pair remains on each atom, and the opposite formal charges sum to 0.

6

Final answer

The CO Lewis structure has a C-O triple bond and one lone pair on each atom. Carbon has a -1 formal charge and oxygen has a +1 formal charge.

Formal Charges

AtomFormal charge
C-1
O+1

Common Mistakes

  • CO has formal charges even though the molecule is neutral overall.
  • A double bond arrangement is less useful for the standard Lewis structure.

FAQ

What is the Lewis structure for CO?

The CO Lewis structure has a C-O triple bond and one lone pair on each atom. Carbon has a -1 formal charge and oxygen has a +1 formal charge.

What is the Lewis dot structure for CO?

The Lewis dot structure for CO is the electron-dot drawing shown above. The CO Lewis structure has a C-O triple bond and one lone pair on each atom. Carbon has a -1 formal charge and oxygen has a +1 formal charge.

How many valence electrons does CO have?

CO has 10 total valence electrons in this Lewis structure.

What is the molecular geometry of CO?

CO is a diatomic molecule, so it is linear. VSEPR electron geometry around a central atom does not apply.

Is CO polar or nonpolar?

CO is polar in the Lewis structure shown here. Its molecular geometry is Linear.

References

Method notes are aligned with standard Lewis structure steps: count valence electrons, draw a skeleton, distribute electrons, form multiple bonds when needed, and check formal charges and resonance.

OpenStax Chemistry 2e: Lewis Symbols and Structures and Formal Charges and Resonance.