A carbon compound 'A' is widely used as a preservative in pickles and has a molecular formula C\(_2\)H\(_4\)O\(_2\). This compound reacts with ethanol to form a sweet smelling compound 'B'.
(i) Identify the compound 'A' and write its structure.
(ii) Write the chemical equation for the reaction of 'A' with ethanol to form compound 'B'. State the role of presence of an acid in the reaction.
(iii) How can we get compound 'A' back from 'B' ?
(iv) How can 'A' be obtained from ethanol ?
(v) Name the gas produced when compound 'A' reacts with washing soda.