**Transcription of Educational Content:****Using infrared spectroscopy, how can salicylic acid be differentiated from acetylsalicylic acid (aspirin)?**1. Acetylsalicylic acid and salicylic acid cannot be differentiated via IR spectroscopy as they have all the same stretches present.2. Acetylsalicylic acid will have two carbonyl (C=O) stretches at approximately 1700 cm⁻¹. It will possess one C=O stretch at about 1680 cm⁻¹ for the carboxyl group which is present in both and one unique carbonyl stretch at 1725 cm⁻¹ for the ester functional group.3. Salicylic acid will have a unique aliphatic sp³-hybridized C-H at approximately 3150-3050 cm⁻¹.4. Salicylic acid will have two carbonyl (C=O) stretches at approximately 1700 cm⁻¹. It will possess one C=O stretch at about 1680 cm⁻¹ for the carboxyl group which is present in both and one unique carbonyl stretch at 1725 cm⁻¹ for the ester functional group. In this experiment, we rely upon Infrared (IR) Spectroscopy to confirm that the expected reaction had occurred. Give the two uses of IR in organic chemistry.1) Comparing known to unknown samples (peak by peak match) [fingerprint]2) Determine the melting point of a solid compound.3) Determine the presence or absence of functional groups or bonds in a molecule.4) Isolate particular functional groups for independent characterization.5) Determine the completion of a reaction by comparison of band intensities.

The chemical structures for the salicylic acid and aspirin are shown below. Acetylsalicylic acid has two carbonyl groups which are appeared at approximately 1700 cm-1 and the additional IR peak is appeared at approximately 1725 cm-1 due to the ester group. Therefore (2) is the correct choice.In organic chemistry, IR is used for the determination of the unknown compound that formed in the reaction by comparing known to unknown compound fingerprint region of the IR spectroscopy and in the determination of the presence of the functional group. Therefore, (1) and (3) are correct.