What is the $IUPAC$ name of picric acid?

The product$(s)$ of the reaction is/are:

Which of the following is true regarding the solubility of $p$-nitrophenol and salicylaldehyde in a base?

Which of the following substances is the most acidic?

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$:
Assertion $A$: Aryl halides cannot be prepared by the replacement of the hydroxyl group of phenol by a halogen atom.
Reason $R$: Phenols react with halogen acids violently.
In the light of the above statements,choose the most appropriate from the options given below:

Which of the following products is obtained when phenol is treated with $CHCl_3$ and $NaOH$?