Make Aspirin with Salicylic acid
and ethanoic anhydride (Conc.
Sulphuric acid catalyst).
Recrystalise
my made
aspirin using hot
water as the
solvent.
Test the purity of the
recrystalised aspirin compared
with the un-recrystalised aspirin,
salicylic acid and pure aspirin
using thin layer
chromatography.
Use a colorimeter to
test the concentration of
salicylic acid in the
un-recrystallised aspirin,
by comparing to known
concentrations of
salicylic acid solutions
(using Iron (III) Chloride.
Test the purity of shop
bought aspirin by titrating with
Sodium Hydroxide (assay).
Use Iron (III)
Chloride to test the
purity of my aspirin
qualititively
Back titration- Reflux
aspirin with NaOH and
then titrate with HCl to
see how much NaOH
has reacted.
Melting Point test- see how
the melting points vary,
impurities will have an
impact on the melting point
of the different aspirins.
Chemicals I will need
Chromatography Solvent
Ethanoic anhydride
Glacial Acetic acid?
Shop bought
aspirin tablets
(1 packet)
Pure aspirin powder
Salicylic acid
Iron (III) Chloride
Conc. Sulphuric Acid
Sodium Hydroxide
Hydrochloric acid
Equipment needed
(apart from beakers
etc which I can get
in the lab)
Reflux apparatus
Fume cupboard
Chromatography plates
Pestle and Mortar
Top pan
balance (2 d.p.
minimum)
Filter paper
Buchner funnel
Cling film
Colourimeter
spatula
Weighing boat or one
of the test tubes
which have screw on
lids (Sorry I cannot
remember their
name)