This is a Lab Report on the “Synthesis of Organic Aspirin” Essay Example

starts off by taking salicylic acid and mixing it with the acetic anhydride. To this adding five drops of sulfuric acid and some distilled water gave a forming solid after the solution cooled. The crude aspirin had formed. Since pure aspirin was what we are after, filtration needed to take place.

Filtration is a treatment in which you remove the solid from the water [3].

End of the experiment, heating the recipient allowed it to dry and form an end "powder" substance of purified aspirin. Figure 2 shows the process of filtration. For more precise and descriptive procedure, follow the procedure listed in the University of Winnipeg, Department of Chemistry, Laboratory Manual (2007) for CHEM. 1 1 1/3, page 4-3.

Data and Results

First we need to see if it is balanced.

As shown in Figure 1 we see that the equation is balanced on both the reactant and product side. Since the limiting reagent is the reactant that is completely consumed in the reaction we need to calculate moles. The equation for moles and calculations is listed in the Appendix on this report. Since the salicylic acid is being completely used up in the reaction, this is the limiting reagent. The theoretical yield is the actual mass of the AS in the reaction. For calculations, the moles of salicylic acid (limiting reagent) need to be multiplied to the molar mass of AS.

This gives the theoretical value. In contrast the percent yield explains how far or how close the theoretical value is to the percent error. To calculate percent yield, the mass of the experimented AS needs to be divided by the theoretical value. This gives a

decimal number, in which needs to be multiplied by a hundred to get the yield percentage [4].

The reason why we use cold water in the experiment rather than warm water is to how well we want the precipitate to form. In rationalization if warm water was used then the precipitate might have not formed that well.

Since the product must remain solid and not dissolve cold water was used to basically keep the precipitate [5]. In rationalization the reason that the same filter should be used twice is because when scraping off the aspirin the error is that you never get all of it off the old filter paper. When this happens your mass decreases and inaccurate results will show. When using the same filter paper you are putting the new pure aspirin back on the filter paper where it came from, resulting in no loss of aspirin and the mass remains constant.

Sources of determinate error in this experiment were very easy to make as human errors.

There was accidental error when more than five drops of sulfuric acid was added to the mixture of salicylic acid and acetic anhydride because the turning knob on the burette was faulty. This could have affected my results since sulfuric acid was the catalyst in this reaction causing inaccurate results. When it was time to weigh the filter paper after the dry aspirin was scraped off, the error could be that the water which was likely to still be in the filter paper this could have added more weight to the filter paper alone. This is error because it gives me

However theoretical percentage will remain unchanged because

it is based on the amount of possible product [6].

This could have been solved by letting the filter paper sit on the hot plate for a longer period of time. There were minor human errors like inaccurate measurements due to negligence. The seemingly obvious remedy would be to pay more attention to the experiment and keep a close on eye on it.

Conclusion

Ecstatically acid (AS), or more commonly known as aspirin is synthesized from the reaction of salicylic acid mixing with acetic anhydride. The end product is aspirin, but n the crude form.

Crude is the form of aspirin that contains impure acids, like unrelated sulfuric acid. These impurities need to be separated from the crude aspirin to achieve the pure dry form. This was done through rationalization. Rationalization is the treatment process of taking the crude aspirin which is contaminated with the impure sulfuric and salicylic acid and separating them from the aspirin. The end product is pure dry aspirin in our case. In conclusion I think that the experiment was poorly done with too many errors.

The cause of this could be that I did not pay enough attention or most likely ran out of time at the end of the experiment.