**Distinguishing Molecules Using IR and NMR Spectroscopy**Infrared (IR) spectroscopy is a cost-effective tool commonly used in organic chemistry to identify functional groups within molecules. On the other hand, Proton Nuclear Magnetic Resonance (¹H NMR) spectroscopy provides detailed information about the molecular structure and environment of hydrogen atoms. The choice between IR and NMR depends on the specific differences in the molecular features of the starting material and the product.**Example Reaction:**Consider the following reaction where an organic starting material (on the left) reacts with hydrogen bromide (HBr) to form a product (on the right):```Cyclohexane with a double bond -> Reacts with HBr -> Bromocyclohexane```**Question:**Would IR or NMR be a better choice to distinguish the organic starting material and the product?**Possible Answers:**1. **IR is better because the starting material has a C=C peak around 1600 cm⁻¹ and the product does not.** 2. **IR is better because the product will have a C-Br peak around 2500 cm⁻¹ and the starting material will not.**3. **¹H NMR is better because these two molecules will not show peaks in IR.**4. **Neither IR nor ¹H NMR can distinguish these molecules, they are too similar.****Explanation of Graphs and Diagrams:**1. **Chemical Structures:** - The starting material is cyclohexene, identified by its double bond (C=C). - The product is bromocyclohexane, identified by the presence of the bromine atom (Br) attached to the ring. To distinguish between these molecules:- The **starting material** (cyclohexene) has a characteristic C=C stretching vibration observed in IR spectroscopy at approximately **1600 cm⁻¹**.- The **product** (bromocyclohexane) can be identified by the presence of a C-Br bond, which typically does not have a strong IR absorption around 2500 cm⁻¹, contrary to one of the options.Thus, the best choice would be:**IR is better because the starting material has a C=C peak around 1600 cm⁻¹ and the product does not.**

IR is far less expensive the ¹H NMR and a better choice to distinguish molecules when possible. Consider the reaction below. Would IR or NMR be a better choice to distinguish the organic starting material and the product? + HBr Br 8 IR is better because the starting material has a C=C peak around 1600 cm-¹ and the product does not. IR is better because the product will have a C-Br peak around 2500 cm-1 and the starting material will not. ¹H NMR is better because these two molecules will not show peaks in IR. Nether IR nor ¹H NMR can distinguish these molecules, they are too similar.

IR is far less expensive the ¹H NMR and a better choice to distinguish molecules when possible. Consider the reaction below. Would IR or NMR be a better choice to distinguish the organic starting material and the product? + HBr Br 8 IR is better because the starting material has a C=C peak around 1600 cm-¹ and the product does not. IR is better because the product will have a C-Br peak around 2500 cm-1 and the starting material will not. ¹H NMR is better because these two molecules will not show peaks in IR. Nether IR nor ¹H NMR can distinguish these molecules, they are too similar.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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