$HCOOH$ reacts with conc. $H_2SO_4$ to produce:

The reaction $CH_3COOAg + Br_2 \xrightarrow{CS_2}$ is known as the Hunsdiecker reaction. What is the main product of this reaction?

The increasing order of acidic strength among the following compounds is
$I.$ Benzoic acid
$II.$ $4-$nitrobenzoic acid
$III.$ $3, 4-$dinitrobenzoic acid
$IV.$ $4-$methoxybenzoic acid

When propionic acid is treated with aqueous sodium bicarbonate,$CO_2$ is liberated. The '$C$' of $CO_2$ comes from:

$A$ compound $(A)$ has the molecular formula $C_2H_4O_2$ and it gives the following reactions:
$(i)$ Addition of the above compound to a sodium carbonate solution gives effervescence of $CO_2$ gas and forms compound $(P)$.
$(ii)$ When compound $(P)$ is heated with sodalime,it gives gas $(Q)$. Identify $(A)$,$(P)$,and $(Q)$ and provide the reactions.

What is the name of the reaction: ${C_6}{H_5}CONH_2 \xrightarrow{PCl_5} C_6H_5CN$?