HOW TO CONDUCT EXPERIMENTS

Characterisation and purification of chemical
substances
Experiment 1: (a) To determine of boiling point of an organic
compound
Apparatus required
Aluminium block, capillary tube, fusion tube, thermometer, stand
(with clamp), tripod, and
kerosene burner.
Chemicals required:
Organic liquids such as :
Benzene, Benzaldehyde for
boiling point determination,
Procedure
(1) Take the Aluminium block.
Light the kerosene burner.
(2) Take a capillary tube and
close its one end by holding
the end in the flame for 2-3
minutes.
(3) Transfer a few mL of the
organic liquid compound in
the fusion -tube. Dip the
capillary tube into the liquid
in the fusion tube keeping
the sealed end up.
(4) Put the tube in one of the
holes of aluminium block
and put the thermometer in Fig.1.1: Arrangement showing
boiling point determination
Thermometer
Clamps
Stand
Capillary
Fusion tube
Liquid
Aluminium Block
Tripod
Burner
18 Manual of SEAT Friendly MCL Kit
the other hole. Care should be taken that the liquid is visible in
the fusion tube after it is put in the hole.
(5) Place the Aluminium block on the tripod.
(6) Start heating the block with the help of kerosene burner.
(7) Note the temperature as soon as regular streams of bubbles are
seen out of liquid in the fusion tube.
Observation
1. Boiling point of water = 1000C
2. Boiling point of benzene = 780C
3. Boiling point of Benzalaldehyde = 1780C

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