if ferric chloride was added to an unknown which happened to be benzophenone to identify if it has the phenol functional grp...will the sol'n turn purple (it contains the phenol) or yellow(does not contain phenol)?

Benzophenone is a ketone and ketones don't give a ferric chloride test UNLESS they form the enol tautomer. Does it form the enol? I did not find anything on the Internet to tell me if benzophenone will give a positive ferric chloride test or not. Couple that with the fact that not ALL enols/phenols give a positive ferric chloride test and that leaves me with the suggestion that you try this in the lab. Sorry I can't be of more help.

When ferric chloride is added to an unknown compound to test for the presence of a phenol functional group, a positive result is indicated by the formation of a purple color. In the case of benzophenone, which is a ketone and does not contain a phenol functional group, the solution should not turn purple. However, as you mentioned, ketones can potentially form enol tautomers that can react with ferric chloride, but the formation of an enol tautomer in benzophenone is not favored. As a result, it is more likely for the solution to turn yellow, indicating a negative ferric chloride test (i.e., no phenol group is present). Of course, running the test in the lab is the best way to confirm this prediction.

Based on the information available, benzophenone is a ketone and does not typically give a positive ferric chloride test. However, ketones can form enol tautomers, which may react with ferric chloride. It is unclear whether benzophenone forms the enol tautomer or if it will give a positive ferric chloride test.

To determine if benzophenone has the phenol functional group, it is best to perform an experimental test in the laboratory. Mixing ferric chloride with benzophenone and observing the color change of the solution can help establish whether it contains the phenol group. A positive test would result in a purple color, while a negative test would show no significant color change or a different color, such as yellow.

To determine if a compound contains a phenol functional group, ferric chloride is often used as a test reagent. However, in the case of benzophenone, a ketone compound, the ferric chloride test may not give a conclusive result.

Ketones typically do not react with ferric chloride unless they undergo tautomerization to form the enol tautomer, which contains a hydroxyl (-OH) group. In the enol form, benzophenone could potentially react with ferric chloride to give a positive test result.

To find out if benzophenone can undergo tautomerization to form the enol, you can search for literature sources or chemical databases that specifically discuss the tautomerization of benzophenone. If you were unable to find conclusive information, it indicates that more research may be needed or that the test should be performed in a laboratory setting.

In summary, benzophenone is a ketone that may not give a positive ferric chloride test unless it can tautomerize to form the enol. However, without specific information on its tautomerization, it is advisable to conduct further research or perform the test experimentally in the lab to obtain a definitive answer.