4.2.4 Analytic Techniques Flashcards
What does IR spectroscopy do
identifies particular bonds and identify functional groups
uses of IR spectroscopy
breathalyzers to detect ethanol
More IR radiation absorbed more ethanol in breath
monitor pollutant gases - car exhausts
infra red definition
long wavelength, low frequency radiation
wavenumbers definition
used as a measure of the wavelength or frequency of the absorption
how to answer question on IR spectroscopy
circle and label peaks for these bonds on spectrum
label one if it isn’t present as well
write in table too see which are present for evidence
what direction do the peaks go in if present
downwards
mass spectroscopy
inject gaseous compound
its bombarded with high energy electrons from an electron gain
knocks an electron out causing a positive charge
molecular ion is attracted to the plate and identified
molecular ion peak
M(g) -> M+ + e-
always furthest to the right
ion of the whole molecule / molar mass of whole molecule
highest mass
produces peak furthest to the right
fragmentation definition
breaking up the whole molecule at just one bond
how to show fragmentation
draw out displayed formulae and draw a zigzagged line through the bond that breaks
one side is positive and its the one that shows on the mass spectrum
what does fragmentation produce
an ion and a free radical
