Some mothballs used when storing clothes are made of naphthalene (C10H8), which has the following incomplete structure.

(a) Add double bonds where needed to draw a complete electron-dot structure.

Video transcript

So everyone's in this video, we're given this incomplete structure. We need to go ahead and add the appropriate double bond student um to complete the lewis dot structure. So here we're dealing with hydrogen, carbon and oxygen atoms. So oxygen prefers to have two bonds and two lone pairs to fulfill its octet. The only oxygen atom here in this molecule is this one on top here because it does have two lone pairs. We just need to go ahead and add a pi bond to fulfill its octet. Now, carbon likes to have four bonds. We can see here that we only have three bonds for now. So we need to add a additional bond to go ahead and fulfill its octet. So how we can do this in a ring form is by adding alternating double bonds. So for carbon ring on the left side here we go ahead and add one here and then like I said, we'll go ahead and add alternating double bonds. So skip the next angle here, then add one gear and hear the same thing for the ring on the right side. We'll have one here here and here. Now. We see that all the carbon has its four different bonds as well as our oxygen having two bonds for hydrogen. It needs to fulfill a duet rules of the octet rule, which means that it only needs two valence electrons to be happy because it only needs two electrons, it has to be terminal and we see that all hydrants do have a bond. So those don't need any double bonds. So this is going to be our complete lewis dot structure for our molecule of benzene in.