organic analysis Flashcards
mass spectrometry
- analysis tool to identify unknown samples using unique mass spectrum
-measures mass to charge ratio (m/z)
mass spectrometer - instrumentation
ionises, accelerate, deflects and detects an atom or molecules so that mass to charge ratio is measured
- produces positive charged fragment
base peak
highest peak - largest absorbance and intensity
molecular ion peak
shows the molar mass of compound / highest m/z
why is there a small peak after molecular ion peak
an isotope (often carbon)
fragmentation
M+ -> X+ +R.
region of electromagnetic spectrum used in IR
infrared
region of electromagnetic spectrum used in NMR
radio waves
principles of spectroscopy
atoms/ molecules absorb and emit electromagnetic radiation of specific energies
purpose of IR
information about covalent bonds and functional groups present in organic molecule - identify structure and type of molecule
features of IR
expensive
fast
absorption spectroscopy
uses of IR
- identify of organic compounds
-design new drugs
-tests for blood alcohol
IR spectrum analysis
- specific covalent bond represents each peak
- a bond that vibrates at higher frequency absorbs IR radiation with higher wavenumber and greater energy bond
-must specify the O-H bonds but not as necessary for other types
NMR
-operates in radio waves
-form of absorption spectroscopy
-very fast and very expensive
- qualitative - structure of compound
principles of nuclear spin and NMR
- in order to interact with radio waves atoms must have nuclear spin
- in presence of external magnetic field nuclei line up in unstable arrangement
- normally in low energy state and aligned with strong magnet
NMR
ANALYSES THE H OR C ENVIRONMENTS
chromatography
- technique used ti seperate substances present in a mixture
- can detect the presence of a particular substance/ structure and concentration
common uses of HPLC
-COVID tests and pregnancy
- drugs present in blood
how chromatography works
- each substance analyses the different rates they move along the stationary phase depending on strength and solubility of mobile phase
-absorption to sp and desorption into mobile phase