Radicals' formation

If carbon atom is tetravalent while oxygen atom is divalent so when they combine together the result should be $\ce{C2O4}$ then how are there compounds of formulas with $\ce{CO2}$, $\ce{CO3}$ and others? How do they bond?




[![enter image description here](https://i.stack.imgur.com/ZBBjT.png)](https://i.stack.imgur.com/ZBBjT.png)


This is the lewis structure of $\ce{CO\_2}$.Each bond symbolises of sharing of two electrons.One from oxygen and other from carbon.


[![enter image description here](https://i.stack.imgur.com/FGdXF.png)](https://i.stack.imgur.com/FGdXF.png)


You can imagine $\ce{CO\_2}$ as such.


**Your confusion**
==================


[![enter image description here](https://i.stack.imgur.com/jQpOk.gif)](https://i.stack.imgur.com/jQpOk.gif)


[![enter image description here](https://i.stack.imgur.com/OXo1g.png)](https://i.stack.imgur.com/OXo1g.png)


Are you thinking something like this should be happening?[![enter image description here](https://i.stack.imgur.com/dhVXi.png)](https://i.stack.imgur.com/dhVXi.png)


Formation of $\ce{CO\_2}$ can be calculted by transfer of valencies but cannot be explained.
And there are other compounds which cannot be calculated by valency transfer but can be explained by Kossell-Lewis approach.


[![enter image description here](https://i.stack.imgur.com/2dFBc.gif)](https://i.stack.imgur.com/2dFBc.gif)


**Transfer of valencies only calculate and predict the formation of a compound.It does not explain.**


**$\ce{CO\_2}$ is not a radical**



> 
> In chemistry, a radical (more precisely, a free radical) is an atom, molecule, or ion that has unpaired valence electrons. Like this.  
> 
> [![](https://i.stack.imgur.com/Izra5.png)](https://i.stack.imgur.com/Izra5.png)
> 
> 
> 


 3