BTEC APPLIED SCIENCE: Unit 4C Making headache tablet

Making a headache tablet
How to get a melting point for aspirin
(mainly in a laboratory):
1. Get the equipment ready such as the capillary tube,
the aspirin made and the melting point apparatus.
2. Take a capillary tube from the teacher and gently
press the opening end into the aspirin crystals you
made so that a few powdered aspirin will enter the
line.
3. Once it enters the tube, tap the tip of the capillary
tube so that the aspirin will firmly pack at the bottom
(it should have a depth of 1-2mm).
4. Put the capillary tube with aspirin into the melting-
point apparatus.
5. Observably, for the aspirin, if it starts to melt, record
the temperature immediately and wait till it
completely melts and re-records the temperature for
you to have a melting-point temperature range
(135oC is the expected melting point for purified
aspirin)
If the melting point is higher than it is supposed to be, the
salicylic acid didn’t fully dissolve, or it’s still present that
hasn’t fully reacted to form purified aspirin. If the melting
point temperature is lower than 135 oC, impurities are
present with your aspirin.
Conclusion about the purity of the
aspirin:
When we measured melting points, we got a range of 125
to 150 degrees Celsius. Our melting point for this