1. • 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.
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2. Week 20
Stretching and bending vibrations resulting from the absorption of infrared
radiation
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3. Schematic diagram of an infrared spectrometer
Week 20
Schematic diagram of an infrared spectrometer
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4. A typical infrared spectrum showing absorption peaks
Week 20
A typical infrared spectrum showing absorption peaks
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5. Week 20
• Identify, using C=O and O–H absorptions, an alcohol, an aldehyde or ketone and a carboxylic acid.
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6. Infrared spectrum of methanol
Week 20
Infrared spectrum of methanol
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7. Infrared spectrum of propanal
Week 20
Infrared spectrum of propanal
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8. Infrared spectrum of propanoic acid
Week 20
Infrared spectrum of propanoic acid
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9. • 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.
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10. The mass spectrum of magnesium
Week 20
The mass spectrum of magnesium
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11. 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.
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12. Mass spectrum of ethanol
Week 20
Mass spectrum of ethanol
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13. Mass spectra of the isomers of C5H12, pentane and 2-methylbutane
Week 20
Mass spectra of the isomers of C5H12, pentane and 2-methylbutane
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14. Week 20 Spectra A and B © Pearson Education Ltd 2008
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15. 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.
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16. Mass spectrum for an unknown alkane
Week 20
Mass spectrum for an unknown alkane
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17. Week 20
Equations explaining how some of the peaks arise in the mass spectrum for
hexane
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18. Mass spectrum of pent-1-ene
Week 20
Mass spectrum of pent-1-ene
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19. Mass spectrum of an alkane
Week 20
Mass spectrum of an alkane
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