in this video we're gonna focus on naming alkynes so let's begin with the common names how can we name this particular alkyne this is C - H - and its common name is acetylene now this is also called a sign because it's an alkyne so it ends with the suffix yne but the common name is acetylene now let's try another example what do you think the common name is for this molecule so here we have the acetylene portion of the molecule which is the C triple bond C part and notice that we have a methyl group in front so therefore the common name for this alkyne is simply methyl acetylene so based on that example go ahead and try this one so write the common name for this molecule so let's focus on the acetylene portion of the molecule and notice that we have a methyl group on the left and on the right so therefore this is going to be called dimethyl excitedly dimethyl acetylene and so hopefully you're getting the hang of how to write the common names of our kinds now let's move on to our next example which is going to be ch3 ch2 C triple bond CH so go ahead and write the common name for that alkyne and also write thigh you PAC name since we're here already let's go ahead and do that let's start with that you PAC name actually so this is carbon one two three four so four is associated with butane but instead of writing butane we're gonna write butane now the triple bond is on carbon one so this is called one view time now what is the common name of this particular alkyne so we can see that we have our acetylene group and this is an ethyl group attached to it so the common name is going to be ethyl acetylene and so that's it for this example here's another one so for this example right the IU PAC name and also the common name of this particular alkyne so let's start with the IU PAC name we need some number in such a way that the alkyne has the lowest possible number so this is going to carbon 1 2 3 4 5 so that's a pentane but instead of saying pentane it's gonna be pent on now the triple bond is between carbons 2 & 3 so we have to pick the lower of those two numbers so this is going to be called 2 pen time now let's try the common name so here is our acetylene functional group and on the left side we have a methyl attached to it and on the right side we have an ethyl group attached to it so we need to put it in alphabetical order so the common name is ethyl methyl acetylene now for this next example all I want you to do is to write the common name so let's say that we have a benzene ring attached to the carbon-carbon triple bond how can we name it so notice that whenever you have a benzene ring as a substituent it's called phenyl so to name this it's simply going to be phenol acetylene and for the common name you need to write it as one word so if you see me put a space it really should be together as one word so just keep that in mind now let's work on another example so for this one right the common name and the I you pack name as well so let's start with the I you pack name this is going to be carbon one two three four five six so we have a methyl on carbons two and five so it's going to be two five dimethyl and four six carbons that's hexane but we're going to use hex I and the triple bonds on carbon three so it's gonna be - three - hex sign and so that's how you can name this particular our time now what is the common name for this particular molecule so notice that we have an isopropyl group on the left side and on the right side so this is going to be called dye isopropyl acetylene now let's work on one final example what's the common name for in this molecule so we have two phenyl groups attached to the acetylene part so it's simply going to be diphenyl acetylene now let's work on some more examples with our u-pack nomenclature so go ahead and write the IU pack name for this particular alkyne now should we number it from left to right or right to left if we go from right to left the triple bond will be on carbon dream and if we go from left to right the triple bond will still be on carbon three so which way should we go going from left to right we're going to have the name 2-chloro and then we have a methyl group on carbon 5 so it's going to be 5 methyl and we have the alkyne on carbon 3 so that's going to be 3 hex on because we have 6 carbons in the parent chain now if we go in the other direction this will be 1 2 3 4 5 6 so chloro still comes before methyl we still need to put it in alphabetical order but it's gonna be 5 chloro - 2 methyl - 3 hack sign and so the first one is gonna win because you want the first of excuse me the first substituent to have the lower number and so this is the right answer now let's move on to our next example so it's going to be ch3 ch2 - CH with a ch3 attached to it and then we have our carbon-carbon triple bond and another triple bond at the end so go ahead and name that molecule so because we have the chill bond at the end here we want to start counting from right to left we want to give the triple bond the lower values so we have a nine carbon chain that's the longest chain and so that's gonna be non name but instead of nonane is gonna be none nine we do have two alkynes or two triple bonds so it's gonna be a dye I so let's put it all together we have a methyl group on carbon 7 so it's seven methyl and then we have a triple bond by carbon one and five so it's gonna be 1 comma 5 Nana and then dye I because we have two triple bond functional groups and so this is how we could name this particular molecule now what do you do when you have a molecule that contains an alkyne functional group and an alkyne functional group which one has more priority should we place the one at the alkyne or at the alkyne in the situation such as this the alkyne has more priority so we're gonna count given the alkyne the lower number so we have six carbons so this is hexane but it's gonna be hexene instead now the way you name it it's gonna be one heck seen because the alkyne is a carbon one and then - five iron because the triple bond is on carbon five and so that's how we can name a molecule that has an alkene and an alkyne functional group now what if we have an alkyne with an alcohol functional group which one has more priority the alcohol or the alkyne it turns out that that alcohol has a higher priority than the alkyne so we're gonna give the O age group the lower number so this is called 3eu time cuz the alkyne is on carbon 3 and then - 2 all because the alcohol is on carbon 2 and so that's how we can name this molecule now let's try one more example go ahead and name this particular molecule so how should we count it should we count it like this 1 2 3 4 5 6 7 8 or should we count it like this 1 2 3 4 5 6 7 when you count the longest chain it has to include the alkyne functional group so we need to use the numbers in green so this is carbon one two three four five six and seven now we have a propyl group on carbon 3 so this is going to be called 3 propyl - one peptide since we have a seven carbon chain with the alkyne functional group and the triple bond is that carbon one and so that's it for this video so now you know how to name alkynes using IU pack nomenclature and you know how to write the common names for Al Quaeda molecules thanks for watching