The correct order of their reactivity towards hydrolysis at room temperature is:

What are $X$ and $Y$ respectively in the following reaction sequence?
Styrene $\xrightarrow[(ii) H_3O^+]{(i) KMnO_4 / KOH} X$ $\xrightarrow{Br_2 / FeBr_3} Y$

Formic acid on heating with concentrated $H_2SO_4$ at $373 \ K$ gives $X$,a colourless substance and $Y$,a good reducing agent. The number of $\sigma$ and $\pi$ bonds in $X$ and $Y$ are respectively:

$A$ carboxylic acid is converted into its anhydride using:

What is the correct order of acidity of compounds $(I)$,$(II)$,and $(III)$?
$(I)$ $4$-Nitrobenzoic acid
$(II)$ $4$-Methoxybenzoic acid
$(III)$ Benzoic acid

What is the name of the class of products formed in the reaction $RCOOH + H_2N\phi \rightarrow RCONH\phi$? [Here $\phi = C_6H_5$]