 So let's actually have a look at an output. So here is the IR spectra for butane to own or to butanone You can see firstly the broad tongue that we would expect Occuring so here is the again the output from the datasheet and When you look at the output from the datasheet the OH groups are up in the 3 to 0 0 mark But so are the carbon hydrogen bonds and this is the problem is when you see a value around here Are you looking at carbon hydrogen bonds or are you looking at the hydroxyl group bonds? And that's why we need to remember that if it's a hydroxyl group The the output is much broader not the spike. So the fact that we have no tongue Means we do not have the OH groups So that's definitely out and that's kind of good because Butan to own would not have it what butan to own does have is a double bonded oxygen to a carbon So if we were to draw that but means for So I'll put my four carbons in to is where the functional group is and the unknown bit means It's a double bonded oxygen There's no other parts to this name so I can just assume that everything else will be Hydrogen so now that we've drawn this molecule. Let's see if our Infrared display actually helps us to identify all of these things So we've already said that this region around the 3000 mark is our carbon hydrogen bond and we certainly have plenty of those we've got this really Nice peak down at around 1718 and what you can notice is that that peak around 17 1718 falls beautifully into the range for our carbon double bonded oxygen We definitely have one of those so we have one of those we've identified one of these We've got this whole mess in this little region here. I have to say sometimes this can be a little bit tricky for you to Interpret for example, we've got a a carbon-carbon bonds We know that there are definitely carbon-carbon bonds and they occur between 750 and 1100 and there's a few of those in there Also in this region we would sometimes find carbon-carbon double bonds That's really sitting in the 16 20 to 16 80 region. So that's really more up Here and you can see there's really not much going on up here, but what about the carbon oxygen bonds between a thousand and 1300 sort of hard to detect what's going on here So again as we've talked about previously there can be some Ambiguities that you're looking at when you start to analyze these different types of spectra Sometimes because the region's overlap you need more than one type of spectra in order to pull all of these together So I think what we probably need to do is to have one final Video in this series, which looks at all of this spectra together and how we interpret them In order to build a picture of exactly what molecule we have IR are a bit of fun and usually they have a nice output that gives us some nice clear regions and obviously what you want to do is look at a range of different compounds in order to try and get a sense of How each of the spectra differs for different sets of compounds and that's something that we will have to do A little bit more of during class time, but thanks for watching