Given the following structure: ${\mathrm{CH}}_3-{\mathrm{CH}}_2-{\mathrm{CH}}_2-{\mathrm{Br}}_1$, which functional group is present in this molecule?

• A. Alcohol
• B. Ether
• C. Aldehyde
• D. Alkyl halide

Answer: (D)

Verified step by step guidance

1. Identify the given structure: it is CH\_3-CH\_2-CH\_2-Br, which is a three-carbon chain with a bromine atom attached to the last carbon.
2. Recall the definition of functional groups: they are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules.
3. Analyze the functional groups listed as options: Alcohol contains an -OH group, Ether contains an oxygen atom connected to two alkyl or aryl groups (R-O-R'), Aldehyde contains a carbonyl group (C=O) bonded to at least one hydrogen atom.
4. Compare the given structure to these functional groups: since the molecule contains a bromine atom attached to an alkyl chain, it does not have -OH, oxygen in the middle, or a carbonyl group.
5. Conclude that the functional group present is an alkyl halide (haloalkane), characterized by a halogen atom (in this case, bromine) bonded to an sp3 hybridized carbon atom.