Analytical techniques Flashcards
What do covalent bonds in all molecules absorb and what does the absorbed energy make the bonds in the molecules do?
vibrate more strongly
what does each chemical covalent bond absorb?
A different wavelength of infrared radiation (according to the frequency at which it vibrates)
What is are the 2 types of vibrations?
Stretching and bending
what happens when infrared light is passed through a molecule?
The waves tell us which bonds are present in that molecule
What are the dips in the infrared spectrum graph known as?
peaks and the wave number which the peaks occur is used to identify the types of bonds present in the molecule
What is the fingerprint region unique to?
A particular molecule and is used to identify known substances from a database
What can the IR spectrum be used to do?
To identify which functional group (s) a molecule has
what are the uses of IR spectrum?
-Monitor air pollution by measuring the concentration/abundance of atmospheric pollutants (CO and NO)
-Breathalysers when testing drivers over the alcohol limit
What also absorbs infrared radiation and what does this do? (environmental issues concerning infrared radiation).
absorb IR radiation at a given frequency. The bonds in greenhouse gases in the -Earth’s atmosphere also absorb IR. This gives the molecules increased vibrations. -Collisions between molecules transfer the energy to others, and so the average thermal energy and therefore temperature increase.
-This results in the increase in atmospheric temperature known as global warming.
What are the similarities and differences I can use to comment on between two spectra?
-both show…
-both from a molecule with an….
bother spectra’s have different fingerprint regions and therefore must be different…
What are limitations of infrared?
difficult to identify
