Final answer:
Butane exists as two true isomers, n-butane and isobutane (2-methylpropane), which have the same molecular formula, C4H10, but different structural arrangements.
Step-by-step explanation:
Butane indeed exists as two isomers, n-butane and isobutane. As such, the statement is true.
n-Butane is an unbranched alkane with a straight chain of four carbon atoms. In contrast, isobutane, also known as 2-methylpropane, has a branched structure, where the central carbon atom is bonded to three other carbon atoms. Both compounds have the molecular formula C4H10 but differ in the spatial arrangements of their atoms.
The term 'isomers' refers to molecules that have the same molecular formula but different structures. This concept is fundamental to understanding how different compounds with the same formula can exhibit different properties, as is the case with the two isomers of butane.