IR Spectroscopy Worksheet

IR Spectroscopy Worksheet

Read each question carefully and answer to the best of your ability. Use your knowledge of Infrared (IR) Spectroscopy to analyze the given scenarios and spectra.

1. Which of the following types of molecular motion is primarily responsible for IR absorption?

2. What is the typical wavenumber range for the 'fingerprint region' in an IR spectrum?

1. For a molecule to be IR active, it must possess a change in   during a vibration.

2. The region above 1500 cm⁻¹ in an IR spectrum is often referred to as the   region, where characteristic functional group absorptions are observed.

3. The stretching vibration of a C=O bond typically appears around   cm⁻¹.

1. Briefly explain the fundamental principle behind Infrared (IR) Spectroscopy.

2. Describe two factors that influence the position (wavenumber) of an absorption band in an IR spectrum.

1. All molecules absorb IR radiation.

2. A strong, broad absorption band around 3300 cm⁻¹ is typically indicative of an O-H stretch.

1. An unknown organic compound shows a strong absorption band at approximately 1715 cm⁻¹ and another broad absorption band centered around 3300 cm⁻¹. Based on this IR data, propose a possible functional group present in the compound and explain your reasoning.