why is but-1-ene a structural isomer of 2-methylpropene?
Both have the formula of C4H8
But-1-ene and 2-methylpropene are structural isomers because they have the same molecular formula (C4H8) but differ in the arrangement of their atoms. To understand this, we need to analyze the structures of both compounds.
But-1-ene (also known as 1-butene) has a linear chain of four carbon atoms, with a double bond between the first and second carbon atoms:
CH3—CH=CH2
On the other hand, 2-methylpropene (also known as isobutylene) has a branched structure. It contains a three-carbon chain with a double bond between the first and second carbon atoms, and a methyl group (CH3) attached to the second carbon atom:
CH3
|
CH2=C—CH3
By comparing the structures, we can see that but-1-ene and 2-methylpropene have different connectivity of carbon atoms. But-1-ene has a linear arrangement, while 2-methylpropene has a branched structure. This difference in arrangement results in different chemical and physical properties, which makes them structural isomers of each other.
In summary, but-1-ene and 2-methylpropene are structural isomers because they have the same molecular formula (C4H8) but differ in the arrangement of their atoms, specifically in the carbon-carbon connectivity.