Transcript Microscale reflux

Melting point
determination
Why take melting point?
To help identify sample
To check purity of sample
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Filling sample holder
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dip the open end
of the capillary
into dry, powdered
sample
several times,
shoving more in
each time
Packing the sample
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drop the capillary
(closed end down)
through a long glass
tube
several times
until sample is
compacted at the
bottom
Turn machine on, and
set resistor for temp range
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ON button
indicated
by white arrow.
Set dial
to expected melting
range
How to determine the right setting
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This chart shows
heating curves
at various settings.
For accurate m.p.
determination
the expected m.p.
is on the flat
part of the curve
Taking m.p.
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Turn on
the digital
thermometer
Taking m.p.
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insert
up to 3
samples
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Wait for
and watch
samples melt.
Record
melting range