For a covalent bond vibration to absorb infrared (IR) radiation, the vibration must cause a change in the molecule's dipole moment. Which of the following vibrations does not result in the absorption of infrared radiation?
The stretching vibration of the C−HC-HC−H bond in trichloromethane.
The stretching vibration of the C−OC-OC−O bond in ethanol.
The stretching vibration of the C≡CC\equiv CC≡C bond in hex-3-yne.
The stretching vibration of the C=OC=OC=O bond in propanal.
21 exam-style questions on AQA A Level Chemistry Organic analysis, covering Identification of functional groups by test-tube reactions, Mass spectrometry, and Infrared spectroscopy. Each one has a worked solution and a mark scheme showing where the marks go.