The IUPAC name for the compound CH3CH=CH2 is prop-1-ene.
To understand this name, we first need to analyze the structure of the compound. CH3CH=CH2 indicates that we have a three-carbon alkene. The ‘CH3’ represents a methyl group, the ‘CH’ between the two groups indicates a double bond, and the ‘CH2’ shows there are two hydrogens attached to the last carbon.
In IUPAC nomenclature, the parent chain is the longest continuous carbon chain containing the double bond. Since there are three carbons, we use ‘prop’ to indicate that it’s a propene. The ‘1’ in ‘prop-1-ene’ signifies that the double bond starts at the first carbon in the chain. Hence, we conclude that the full name is prop-1-ene.