In this example question it says, provide a common name for the ketone shown. Alright. So here goes our ketone structure. In step 1, we have to identify the 2 alkyl groups connected to the carbonyl carbon. Remember, your carbonyl carbon is just a carbon double bonded to the oxygen. Connected to it is this alkyl group, which is one carbon, that's a methyl group, and then we have this carbon chain here. It consists of 3 carbon atoms. 1, 2, 3. So that would be propyl. So we've identified the 2 alkyl groups connected to my carbonyl carbon.
Step 2, name the alkyl groups alphabetically as substituents. Kind of jumped the gun here, we have already identified them as methyl and propyl. Now if they are identical alkyl groups, we use a numerical prefix di. So if they both were methyl groups, we'd say dimethyl. If they both were propyl groups, we'd say dipropyl.
Step 3, we end name of the compound with ketone, and write the names with spaces. So alphabetically, m comes before p, so this would be methyl propyl ketone. So its common name will be methylpropylketone.
