Identification of Polar Molecules & Vibrations: Functional Groups & Infrared Spectroscopy, Slides of Organic Chemistry

Download Identification of Polar Molecules & Vibrations: Functional Groups & Infrared Spectroscopy and more Slides Organic Chemistry in PDF only on Docsity! Functional Groups and Infrared Spectroscopy docsity.com Organic Molecule Classes Nonpolar Polar C C H H H H C C HH C C H H H H H H C C C C C C H H H H H H Alkane Alkene Alkyne Aromatic Dashed Line (ends & bends are carbon) OH O NH2 O O Alcohol Ether Amine Aldehyde Ketone docsity.com Functional Groups -(CH2)nCH3 Alkyl group (found in almost everything) C=C Alkenyl group (found in alkenes) C≡C Alkynyl group (found in alkynes) -OH Hydroxyl group (found in alcohols and carboxylic acids) >C=O Carbonyl group (found in aldehydes, ketones, carboxylic acids, amides and esters. -NH2 Amino group (found in amines and amides) -C≡N Nitrile (or cyano) group (found in nitriles) -R docsity.com Characterizing Functional Groups • Bond types exhibit characteristic vibrations that vary little with environment – OH – C=O – etc • Larger groups exhibit more context-dependent vibrations • Vibrations occur with energies in the infrared range of the electromagnetic spectrum – Absorbance of particular wavelengths indicates functional group presence – Reference spectra can confirm (fingerprint) identity docsity.com Spectroscopy (General) • Spectroscopy is the study of the interaction between energy and matter • Different energy types are used in different types of spectroscopy Low energy- stimulates vibrations Moderate energy- stimulates electronic transitions Lower energy- stimulates nuclear spins docsity.com