Which of the following is the structural formula for butene?

Butene is an alkene with the molecular formula C4H8, featuring a double bond between carbon atoms in its structure. The two structural formulas provided, CH3-CH2-CH=CH2 and CH2=CH-CH2-CH3, both represent valid structural representations of butene.

The first structure, CH3-CH2-CH=CH2, indicates a double bond between the third and fourth carbon atoms, implying that it is 1-butene. In this arrangement, the first carbon is bonded to three hydrogens and connected to the second carbon, which in turn is connected to the third carbon that has the double bond connecting to the fourth carbon.

The second structure, CH2=CH-CH2-CH3, shows a double bond between the first two carbon atoms, designating it as 2-butene. Here, the first carbon is bonded to two hydrogens while directly connecting to the second carbon, which is then followed by a single bond to the third and fourth carbons.

Since both structures accurately depict configurations of butene, choosing both as correct is justified. Understanding that butenes can be distinguished by the position of their double bond enhances one’s comprehension of structural isomer