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Compare the techniques and methods I used to measure the purity of a sample of aspirin.

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´╗┐Compare the techniques of measuring the purity of aspirin I am going to compare the techniques and methods I used to measure the purity of a sample of aspirin. I am going to talk about the good points and bad points of the techniques which I used. TLC Plate Chromatography The TLC Plate Chromatography method had its good points and its bad points. The good points about this technique were that you can estimate whether a sample of aspirin is pure or un-pure pretty easily. This is because the further up the sample reaches on the plate, that?s how pure it is. However this technique has a few bad points to it. Firstly we can?t achieve an exact estimate of the purity of the aspirin, it only gives a rough idea as to whether it consists of many impurities or if it is pretty pure. ...read more.


An un-pure sample will tend to melt over a range of degrees. I feel this technique is good because it is really quick and simple. However there is still chance for human error, if the temperature is not read correctly. Conclusion In conclusion I feel that the melting point was the best and the most accurate method of estimating purity of aspirin. This is because it does not consume much time and also it is really easy and simple. All that needs to be done is read the temperatures and it will show you whether the sample of aspirin is pure or not. TLC Plate Chromatography This method I think was fairly accurate because it showed the difference between the pure and the impure sample of aspirin. However it can?t be exactly precise to the percentage of purity. ...read more.


read of the exact end point result The amount of the phenolphthalein indicator used could either be too much or too less for the practical experiment Therefore basically for the titration practical?s you have to ensure to get accurate results you look closely at any measurements Melting point The melting point technique is fairly accurate however it could also lack errors. If I did not know of the actual melting point of a particular substance and I just tried random temperatures, it could tamper with the substance and my results. Whilst reading the temperature you might read it a few degrees above or a few degrees below. This would not melt the substance properly and wouldn?t provide you with accurate results. None of the results I obtained will be absolutely accurate because there could have been some sort of errors which occurred. I evaluated the techniques I used and discussed where they could lack in accuracy. ...read more.

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