Is this an aldehyde?

$\ce{CH3CH2CH2CHO}$  

I think it is an aldehyde but I saw somewhere that it might be an alcohol... 


I believe that it looks like this. Is that correct?  

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




That's an aldehyde as it contains ($\ce{-CHO}$) group.


Its not an alcohol because in alcohol the carbon and oxygen bond in a single (sigma) bond whereas in aldehyde it is a double bond.


$\ce{CH3CH2CH2CHO}$ cant be a alcohol because as you can see that the terminal carbon is attached to only 3 groups ($\ce{C}$, $\ce{H}$ and $\ce{O}$) which means that it is still missing 1 bond to complete its octet. Therefore this carbon makes one more bond, a double bond, with the oxygen atom to complete its octet and the oxygen also attains a complete octet by this. 


 5