From the results of the melting point of the AE1, the identity of the unknown is 2-chlorobenzoic acid. The melting point for this compound was 143 degrees celsius and in the experiment protocol it was 142 degrees celsius. The less than two degree difference reaffirms that the unknown was a pure compound. The next step of calculating the percent recovery could have been caused by human error. During the extraction and filtration, it is possible that the solution did not become fully acidic by HCl before being left to cool, which would affect the product’s ability to recrystallize. In addition, this reasoning could also be applied to the OL1 recovery rate of 77.87%. The percentage could have been due to a lack of acidity or it could have been caused by the CaCl2 and NaHCO3 being unable to fully separate the compound from the solvent ether. The lack of acidity and insufficient separation of the compound would affect the amount of solute able to recrystallize and would further affect the recovery rate. The melting point of benzil was 95-96 degrees celsius, which is in the range of its known boiling point, therefore the compound is pure. The purified melting point reaffirms that the crystals were successfully purified because the melting point has less than a 2 degree celsius difference. The identity of compound AE1 is 2-chlorobenzoic acid and the identity of the compound in OL1 mixture is benzil.
Comments
Chemical formula
Writing out the name of the chemical followed by the chemical formula would be benefitial to readers that don't know what chemical is associated with the chemical formula.
Suggestions
Although you probably describe what AE1 and OL1 are in your writing of other paragraphs, I would specify in the first sentence that AE1 is a mixture by rephrasing as "...results of the melting point of the AE1 mixture..." Celsius should also be capitalized if the word is being used in full.
Comment
I noticed in your first and second sentences that you used both past and present tense by using "is" and "was." I believe using the word "is" is the most appropriate here because the identity and melting point still apply to your unknown.