CHEM 2444 Chapter Notes - Chapter 14: Infrared Spectroscopy, Electromagnetic Spectrum, Spectroscopy
Document Summary
Chemists make use of the electromagnetic spectrum to probe the structure of organic molecules. Mass spectroscopy: bombarding a molecule with 70 ev of energy leads to formation of a molecular ion. Use the empirical formula to determine the number of rings and/or pi bonds as a prelude to looking for the functional group. Infra-red spectroscopy: absorption of ir light leads to molecular vibrations, particularly in bonds that are polarized and/or exhibit a change in dipole upon absorption of the light. Matching peaks in the ir spectrum with functional group correlation tables allows one to determine the presence of absence of functional groups in an organic molecule. When this proton is irradiated with energy in the radio signal range, that energy, for a given magnetic field strength, induces the proton to flip its spin state. Each different proton will lead to a different signal in the nmr spectrum.
