What is the common name of $Benzene-1,3-diol$?

How can phenol and cyclohexanol be distinguished?

If the reaction sequence given below is carried out with $15$ moles of acetylene,the amount of the product $D$ formed (in $g$) is. . . . . The yields of $A, B, C$ and $D$ are given in parentheses. [Given: Atomic mass of $H=1, C=12, O=16, Cl=35$]

Which group is present in phenol? What is the effect of this group on the ring and its reactions?

In the given conversion,the compound $A$ is:

Phenolphthalein is obtained by heating phthalic anhydride with conc. $H_2SO_4$ and