Study Set Content:
· Carried out by adding a suitable solvent to the mixture. The solvent dissolves the impurity but not the substance being purified. The substance is then separated form solution by filtration.
Filtration
· To separate an insoluble solid from a liquid particularly when the solid is suspended throughout the liquid. The solid/liquid mixture is called a suspension.
· There are many small holes in the filter paper.
· Allow very small particles of solvent and dissolved solutes to pass through as filtrate.
· Larger insoluble particles are retained on the filter paper as residue.
Filtration
· The method of choice to remove solid impurities form
an organic liquid. The impurity can be a drying agent
or an undesired side product or left over reactant
Gravity Filtration
· is
used to separate insoluble impurities from a hot
solution. Hot filtration requires fluted filter paper and
careful attention to the procedure to keep the
apparatus warm but covered so that solvent does not
evaporate.
Hot Gravity Filtration
Never heat organic solvents with a
Bunsen burner
Never heat organic solvents with a Bunsen burner.
Use
a hot plate or hot water bath on a hot plate
· , the solution to be filtered is drawn
through the filter paper by applying a vacuum to a
filter flask with a side arm adaptor (also known as a
Buchner Flask)
Vacuum Filtration
· is typically a fast and efficient way
of filtering
Vacuum filtration
· Used for the separation of solid-liquid mixtures that
are stubborn to settle or difficult to otherwise filter.
Centrifugation
It
uses centrifugal force by rapidly spinning samples so
that the solid is forced to the bottom of the tube
Centrifugation
Organic compounds can be classified into
Hydrocarbon and hydrocarbon derivatives
The structural unit
responsible for a given molecule’s
chemical reactivity under a particular
set of conditions
Functional Group
Most HC are
colorless
However, many liquid compound
oxide when they are stored for a long time and these
products are
intensely colored
– Phenol is orange to(blank) in color because of the traces
of air oxidation products.
brown
indicates the polarity of the samples &
intermolecular forces (IMF) between samples & H2O.
Solubility in H2O
4 Intermolecular forces
Ionic, dipole-dipole, hydrogen bonding and London forces
means that the compound can react
exothermically with oxygen.
Flammability
indicates the presence of unsaturation or
high C-H ratio. Higher C-H ratio, higher luminosity
(yellow flame), more sooty.
Ignition Test
Aromatic >
Unsaturated HC
