Errors In Procedure And Creating Point Of A Pure Compound

478 Words1 Page

1. Describe errors in procedure that may cause an observed capillary melting point of a pure compound 1. To be lower than the correct melting point The sample has impurities, the thermometer is not calibrated, or failure to properly clean the watch glass or tubing before packing the capillary tubes which cause some impurities to be present. 2. To be higher than the correct melting point Heating the sample too quickly, the thermometer is not calibrated, or packing the sample too loosely in the capillary tubes. 3. To be broad in range (over several degrees) Using an impure sample, measuring a sample made up of large crystals, or using a large amount of sample size. 6. Compound A and compound B have approximately the same melting point. State two ways in which a mixed melting point of these two compounds would be different from the melting point of either pure A or pure B …show more content…

The mixed melting point will also be broader in range because of the impurities. Pure A and B would have a narrow range melting point compare to broader range of the mixed compound. 11. The melting points of pure benzoic acid and pure 2-naphthol are 122.5 °C and 123 °C, respectively. Given a pure sample that is known to be either pure benzoic or pure 2-naphthol, describe the procedure you might use to determine the identity of the sample. - Mix the unknown sample with pure benzoic acid. This is Mixture A. …show more content…

- Compare Mixture A’s melting point with the melting point of pure benzoic acid. If it is the same, then it is benzoic acid. If the mixture’s melting point is lower, this means it is not benzoic

More about Errors In Procedure And Creating Point Of A Pure Compound

Open Document