How did ethanoic acid get its name as glacial acetic acid?

Which substance is obtained by the reduction of methanal?

What is meant by homologous series of carbon compounds? Classify the following carbon compounds into two homologous series and name them.
$C_{3}H_{4}, C_{3}H_{6}, C_{4}H_{6}, C_{4}H_{8}, C_{5}H_{8}, C_{5}H_{10}$

Vinegar is a solution of

What is the monomer of natural rubber?

$A$ carboxylic acid (molecular formula $C_{2}H_{4}O_{2}$) reacts with an alcohol in the presence of an acid catalyst to form a compound $'X'$. The alcohol on oxidation with alkaline $KMnO_{4}$ followed by acidification gives the same carboxylic acid $C_{2}H_{4}O_{2}$. Write the name and structure of $(i)$ carboxylic acid,$(ii)$ alcohol,and $(iii)$ the compound $'X'$.