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Task 2: Recrystallization Of Benzoic Acid

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Task 2: Recrystallization Of Benzoic Acid
Unit 4B
Task 2
Title
Recrystallization of benzoic Acid
Aim

Equipment
1. Erlenmeyer flask
2. Graduated cylinder
3. Hot plate
4. Small beaker
5. Ice bath (if necessary)
6. Filter paper
7. Buchner funnel
8. Spatula
9. Weighing machine
Method
1. Weighing paper was used to weigh approximately 1.00g of ‘impure Benzoic acid to produce re crystallization’.
2. Moved it to a 125ml Erlenmeyer flask.
3. Poured approximately 20ml of distilled water by using a graduated cylinder to the flask.
4. The mixture went to the boiling point on a hot plate. Whilst it was heated the mixture was stirred and was boiled till the benzoic acid completely dissolved.
5. When the solution was taken off the hot plate it was examined to
…show more content…
If there is a narrow range of melting point this shows that the benzoic acid had high purity. However, a broad range of melting point shows that benzoic acid is still impure.
There were many factors that affected the accuracy of the experiment and one of them was the melting point. This is because whether the melting point was high or low this indicated whether the substance is chemically different. This means the outcome of the experiment may not be pure benzoic acid as it could have been another substance. A low melting point shows that it was not benzoic acid however; our results show that it was pure benzoic acid because it had a high melting point.
Another factor that could have affected the purity of benzoic acid is through the mechanism of which the sunthesis was followed. Usually when compunds are synthesised it uses a long range of mechanisms and this can cause many contaminations because a variety of apparatus are used. There are also, many experimental conditions. There are contaminants that will affect the purity of benzoic acid they cause the product to usually become unsuitable to colour and it can reduce the quantity of benzoic

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