Final answer:
The condensed structural formula of 1-chlorobutane is CH3CH2CH2CH2Cl, which corresponds to option 1, indicating the chlorine atom bonded to the first carbon in a four-carbon chain.
Step-by-step explanation:
The condensed structural formula of 1-chlorobutane represents the structure of the molecule in a simplified way, showing each carbon atom and its directly attached hydrogen and other atoms. To determine the correct formula amongst the presented options, it is essential to understand that 1-chlorobutane is a four-carbon alkane chain where the chlorine (Cl) atom is attached to the first carbon. Starting with the first carbon atom, which has three hydrogen atoms and one chlorine atom, we write CH3 for the first carbon atom, followed by CH2 for the second and third carbon atoms, and finally CH2Cl for the chlorine-attached fourth carbon atom, thus forming the condensed formula CH3CH2CH2CH2Cl, which corresponds to option 1.