• Identify absorption peaks in an infrared spectrum. Week 20 • State that absorption of infrared radiation causes covalent bonds to vibrate. • Identify absorption peaks in an infrared spectrum. • State that modern breathalysers measure ethanol levels by analysis using infrared spectroscopy. © Pearson Education Ltd 2008 This document may have been altered from the original

Week 20 Stretching and bending vibrations resulting from the absorption of infrared radiation © Pearson Education Ltd 2008 This document may have been altered from the original

Schematic diagram of an infrared spectrometer Week 20 Schematic diagram of an infrared spectrometer © Pearson Education Ltd 2008 This document may have been altered from the original

A typical infrared spectrum showing absorption peaks Week 20 A typical infrared spectrum showing absorption peaks © Pearson Education Ltd 2008 This document may have been altered from the original

Week 20 • Identify, using C=O and O–H absorptions, an alcohol, an aldehyde or ketone and a carboxylic acid. © Pearson Education Ltd 2008 This document may have been altered from the original

Infrared spectrum of methanol Week 20 Infrared spectrum of methanol © Pearson Education Ltd 2008 This document may have been altered from the original

Infrared spectrum of propanal Week 20 Infrared spectrum of propanal © Pearson Education Ltd 2008 This document may have been altered from the original

Infrared spectrum of propanoic acid Week 20 Infrared spectrum of propanoic acid © Pearson Education Ltd 2008 This document may have been altered from the original

• Outline the early developments in mass spectrometry. Week 20 • Outline the early developments in mass spectrometry. • Outline the use of mass spectrometry in the determination of relative isotopic masses and for identifying elements. • Interpret mass spectra of elements in terms of isotopic abundances. © Pearson Education Ltd 2008 This document may have been altered from the original

The mass spectrum of magnesium Week 20 The mass spectrum of magnesium © Pearson Education Ltd 2008 This document may have been altered from the original

Week 20 • Use the molecular ion peak in an organic molecule’s mass spectrum to determine its molecular mass. • Explain that a mass spectrum is essentially a molecule’s fingerprint that can be identified using a spectral database. © Pearson Education Ltd 2008 This document may have been altered from the original

Mass spectrum of ethanol Week 20 Mass spectrum of ethanol © Pearson Education Ltd 2008 This document may have been altered from the original

Mass spectra of the isomers of C5H12, pentane and 2-methylbutane Week 20 Mass spectra of the isomers of C5H12, pentane and 2-methylbutane © Pearson Education Ltd 2008 This document may have been altered from the original

Week 20 Spectra A and B © Pearson Education Ltd 2008 This document may have been altered from the original

Week 20 • Suggest the identity of the major fragment ions in a given mass spectrum. • Use molecular ion peaks and fragmentation peaks to identify structures. © Pearson Education Ltd 2008 This document may have been altered from the original

Mass spectrum for an unknown alkane Week 20 Mass spectrum for an unknown alkane © Pearson Education Ltd 2008 This document may have been altered from the original

Week 20 Equations explaining how some of the peaks arise in the mass spectrum for hexane © Pearson Education Ltd 2008 This document may have been altered from the original

Mass spectrum of pent-1-ene Week 20 Mass spectrum of pent-1-ene © Pearson Education Ltd 2008 This document may have been altered from the original

Mass spectrum of an alkane Week 20 Mass spectrum of an alkane © Pearson Education Ltd 2008 This document may have been altered from the original