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How do you remove impurities from aspirin?

How do you remove impurities from aspirin?

In this purification method, the crude aspirin will be dissolved in a small amount of warm ethanol. Water will then be added and the solution will be cooled slowly and then chilled. The acetylsalicylic acid will recrystallize, and the solid impurities (unreacted salicylic acid) should remain dissolved in the solution.

What affects the purity of aspirin?

Weighing, mixing, heating, cooling, filtration, washing and drying are processes that can affect the yield and the purity of aspirin. In the chemical reaction, most of the time the aspirin produced might be impure. Therefore, aspirin must go through another process known as recrystallization.

How does temperature affect the purity of aspirin?

The purity of acetylsalicylic acid was determined by melting point. The melting point range for the acetylsalicylic acid obtained is 144°C-172°C, it is because it contains impurities. The theoretical yield of aspirin is 2.628g, but the actual yield of aspirin obtained is 0.8953g.

What color is pure aspirin?

There will be no colour showed if aspirin is pure. Purple colour was showed if salicylic acid or traces is present in impure aspirin. Then the intensity of colour qualitatively tells how much salicylic acid was present.

What is the percentage purity of aspirin?

99.6 %
The aspirin was 99.6 % pure.

How to improve yield and purity of aspirin?

[…] Rep: ? You get these gems as you gain rep from other members for making good contributions and giving helpful advice. Anyone know how to improve yield and purity of aspirin?

Why do you use recrystallisation to purify aspirin?

The method I used to purify my sample of aspirin was recrystallisation. This is because it is the method used for purifying organic solids. It is also not very time consuming and is relatively easy to do. It yields very good results as recrystallisation serves the purpose of removing insoluble impurities as well as soluble impurities.

How to calculate the molarity of my aspirin?

Since we are looking for the amount of salicylic acid, use the molecular weight of salicylic acid (138.09 g/mol) to calculate the molarity of “My Aspirin” solution. You will end up with 100.00 mL of a 2.37 x 10-2 M “My Aspirin” solution (assuming it is pure salicylic acid).

How much salicylic acid is needed to make aspirin?

During my investigation, I used 10.0534g of Salicylic acid and obtained 11.0062g of Aspirin. The Relative Molecular Mass of Salicylic acid is 138 and the Relative Molecular Mass of Aspirin is 180. Therefore, the theoretical maximum yield is (180/138)* (10.0534) = 13.1131g. The actual yield was 11.0062.