polymers, chirality and chromatography Flashcards
making condensation polyesters (two ways)
- from one monomer containing a carboxyl and an alcohol group
- from two monomers- a diol and a dicarboxylic acid
the monomers are joined by ester linkages
what is condensation polymerisation?
the joining of monomers with loss of a small molecule- usually water or hydrogen chloride
making condensation polyamides (two ways)
- from one monomer containing a carboxyl/acyl chloride and an amine group
- from two monomers- a dicarboxylic acid/diacyl chloride and a diamine
the monomers are joined by an amide bond
acid hydrolysis of polyesters
H+/H2O
reforms a carboxyl group and an alcohol group
base hydrolysis of polyesters
NaOH/H2O
forms an alcohol group and a carboxylate salt (O-Na+)
acid hydrolysis of polyamides
H+/H2O
forms a carboxyl group and a protonated amine group (NH3+)
base hydrolysis of polyamides
NaOH/H2O
forms an amine group and a carboxylate salt (O-Na+)
what is a chiral centre?
a carbon atom that is attached to four different atoms/groups of atoms
optical isomers
stereoisomers that are non-superimposable mirror images of each other
stereoisomers
compounds with the same structural formula but a different arrangement of atoms in space
thin layer chromatography
stationary phase: solid
mobile phase: liquid
separated by: relative adsorption to solid
calculating Rf value
distance moved by component/distance moved by solvent front
gas chromatography
stationary phase: liquid
mobile phase: gas
separated by: solubility
retention time
time taken for sample to travel from inlet to detector
what is GC-MS and why is it useful?
gas chromatography mass spectroscopy
- gas chromatography separates mixtures and mass spectroscopy analyses them
