Question: what is the difference between but 1 ene and but 2 ene?
Answer: In but-1-ene the double bond is present in between the 1st carbon and the second. But in But-2-ene, the double bond is present between the 2nd and the 3rd carbon atom. In but-1-ene the double bond is in between 1st and 2nd carbon atom and in but-2-ene the double bond is in between 2nd and 3rd carbon atom.