Organic synthesis
Read our general notes on Risk Assessment
May I know what are some of the impurities that may be found in preparing my aspirin when its melting point is a shocking 119.8 instead of 135?
Igloo writes
I can understand why you are disappointed with your result, but perhaps it isn’t as shocking as you think. Melting points are often appreciably affected by even relatively small quantities of impurities. In the case of the preparation of aspirin the most significant impurity is likely to be unreacted salicylic acid.
Incidentally, are you sure that your product is completely dry? It is just possible that a little water is present, causing the crystals to dissolve rather than melt.
Risk assessment
Before attempting any practical work based on the advice and suggestions on this website, you must do the following. Identify any hazards, assess the risks from these hazards, and then decide appropriate control measures to reduce the risks. You must have these approved by those in authority in your school or college laboratory. Do not rely on what is said on this website.
For further guidance see our tutorial on Risk Assessment.
Rate this page or react
Share your views on this page, 3 ratings so far
, rated at 
updated: 17 December 2006
