Does phenol belong to alcohols?
No. See: https://en.wikipedia.org/wiki/Phenol
Ok, well that's part of being a successful Chemist right? You have to dig and try and answer it yourself. It's the struggle of trying to do it yourself that makes you become better. Investigate it and based on the data you find, reach some sort of conclusion and then come back and say, "well I think it does based on these facts" or "I don't think it does based on these facts". Even better, propose some sort of experiment to "experimentally" support your conclusions.
I heard somewhere that only when hydroxyl group is bonded to sp3 carbon atom, the organic compound is an alcohol and in phenol, hydroxyl group is attached to sp2 carbon. I wanted to know whether this is true or whether such compounds can also be treated as alcohols.
I don't know the answer without reviewing and I have a chemistry degree. However my point is not so much the answer but I think more importantly how to be a good Chemist. So in that regard, the statement "I heard somewhere" just won't do as it's not quantitative, and Chemistry is all about hard empirical data, what you can prove experimentally. Think of all the great chemists in history and the marvelous chemistry experiments they did. That's what chemistry is all about: where precisely did you hear this? What verifiable reference can you site? What does the Merck Index say? CRC? Others? If you were my student, since you asked, I would ask you to kindly design a (chemical) experiment with say phenol and isopropanol to experimentally confirm one or two interesting properties the later has which the former does not have or something else interesting and then actually do the lab work and write up your results. That's Chemistry. :)
Just trying to help you.
I gave the answer but it was deleted. Donno why. Go ask Berkeman.
As the warning you received explained, insults are never allowed at the PF. You are welcome to re-post without the insults. The rest of your post looked very useful.
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