Formic acid and acetic acid differ in which of the following?

Consider the given reaction: $RCOOAg \xrightarrow{Br_2/\Delta} R-Br$. Which one of the following acids will give the maximum yield of $R-Br$ in the above reaction?

The correct order of acidic strength among the following is:

Which of the following compounds is used as a food preservative?

In the following sequence,products $I$,$J$ and $L$ are formed. $K$ represents a reagent.
$1.$ The structure of the product $I$ is
$2.$ The structures of compounds $J$ and $K$ respectively are
$3.$ The structure of product $L$ is
Give the answer for questions $1, 2$ and $3.$

Number of $CO_2$ molecules evolved upon heating the given compound.