infrared spectroscopy - unit 4 AOS 2

Question 1

infrared spectroscopy

Answer 1

• Infrared spectroscopy is a qualitative analytical technique used to identify the types of bonds types and thus functional groups present in an organic molecule.

Question 2

infrared spectroscopy process

Answer 2

• when organic molecules are exposed to infrared (IR) light, the bonds between atoms absorb this energy.
• Since each bond type absorbs IR light at a unique, characteristic wavelength, the amount of energy absorbed at different wavelengths can be measured to identify the bond types, and hence the functional groups, present in a molecule.
• transmittance and absorbance are inversely proportional
• an infrared spectrometer measures the amount of light that is transmitted but shows absorbance peaks

Question 3

infrared spectrum axes

Answer 3

vertical: transmittance (%)
horizontal: wave number (cm-1)