Draw the Lewis structure for urea, H2NCONH2, one of the compounds responsible for the smell of urine. (The central carbon atom is bonded to both nitrogen atoms and to the oxygen atom.) Does urea contain polar bonds? Which bond in urea is most polar?

Video transcript

Hello everyone in this video. We have to go ahead and draw a lewis dot structure for a hydrogen cyanide. And the formula for that is H C N. So let's first start off by calculating the total number of valence electrons. So again we have the hydrogen atom. Carbon atom as well as our nitrogen atom in this compound. So hydrogen will have one valence electron. Carbon will have four valence electrons sentencing group 48 and our nitrogen will have five valence electrons because it's in group 58. So I these three numbers up, we'll get a total of 10 valence electrons in this compound. Alright, so our hydrogen needs to fulfill its duet rule so it can only be connected to one other atom. So that leaves us just carbon and nitrogen for our central atom. If you compare the electro negativity, our carbon will have a lower electro negativity and therefore it will be the central atom. So here we're gonna go ahead and start figuring out our lewis structure which is just the same as the lewis dot structure. Alright, so again we have a carbon being our central atom. The hydrogen can only form one bond and of course we need at least one bond for our nitrogen. Usually nitrogen will like to have three bonds. Let's go ahead and draw a triple bond. Then in that case each bond has two valence electrons. We have currently 12344 times two is eight. So go ahead. Subtract eight. Leaving us with just two electrons left to use in our lewis dot structure here. So we know that our hygiene is happy because of the duet rule. Our carbon is also happy due to due to the octet rule. And lastly for our nitrogen, we only have six valence electrons surrounding this. So the remaining two will go ahead and be put on our nitrogen. We can put a lone pair here and then this right here will be our final lewis dot structure for hydrogen cyanide.