What is the structural formula for 1-butene?

The structural formula for 1-butene is represented as CH₂=CH-CH₂-CH₃. This notation indicates that the first carbon in the chain has a double bond to the second carbon, demonstrating that it is an alkene, specifically the simplest member of the butene isomers.

In 1-butene, the double bond is located between the first and second carbon atoms, hence the name "1-butene." The formula accurately indicates that there are four carbon atoms in total, along with the right arrangement of hydrogen atoms. The first carbon (terminal carbon) is bonded to two hydrogens (CH₂), the second carbon is bonded to one hydrogen (because it is involved in a double bond), and the remaining two carbons are fully saturated, completing the four carbon chain characteristic of butene.

Understanding the structure helps confirm its nomenclature as the first position of the double bond is critical when naming alkenes. Each carbon is appropriately connected, and the presence of the double bond is visually and structurally clear. This highlights the importance of the proper chemical structure in both nomenclature and in understanding the chemical properties of the molecule.