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is but-1-ene the same as butene

I was looking at my chem textbook today and it showed a diagram of but-1-ene and labelled it but-1-ene but can u just write butene or do u have to show the double bond is between the first and second carbon i.e. but-1-ene
Reply 1
hi, you have to write where the double bond is so yeah but-1-ene same goes for all compounds im pretty sure eg propan-2-ol or 2-methyl butanol and if there’s two groups of something attached like a propane has two chlorines on the first two carbons it would be 1,2dichloropropane
Reply 2
Original post by sglelfe
hi, you have to write where the double bond is so yeah but-1-ene same goes for all compounds im pretty sure eg propan-2-ol or 2-methyl butanol and if there’s two groups of something attached like a propane has two chlorines on the first two carbons it would be 1,2dichloropropane

thanks also for this one can u put the 4 before the pent i.e. 4-pent-en-2-one why is the 4 after?
Reply 3
Original post by Rohan007best
thanks also for this one can u put the 4 before the pent i.e. 4-pent-en-2-one why is the 4 after?

I feel like i haven’t seen this before but you put the number before the suffix so it’s pent-4-en-2-one because the double carbon bond is on the fourth carbon - it’s basically a ketone that is attached to pentene but for some reason it’s got ‘en’ in stead of ‘ene’ idk if that makes sense but yeah whenever u name stuff you put the number of the carbon it’s on before the like prefix/suffix of the group no matter where it is in the word eg 1-chloroethane the 1 goes before ‘chloro’ or 2-methylpropene the 2 goes before ‘methyl’ or pentan-2-ol the 2 goes before ‘ol’ i hope this makes sense 😭

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