Phenol $\xrightarrow[{{H^ + }}]{{CHCl_3/NaOH}}$ Salicylaldehyde. The above reaction is known as:

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 $H=1, C=12, O=16, Cl=35$]

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

What is the correct order of increasing dissociation constant $(K_a)$ for the following compounds?

The decreasing order of acidic strength of different $(-OH)$ groups is:

Phenol on oxidation in air gives