(a) (i) A compound 'X' having two carbon atoms in its molecule turns blue litmus red and 5-8 % solution of 'X' in water is widely used as a…

A compound 'X' having two carbon atoms in its molecule turns blue litmus red and $\displaystyle 5-8 \%$ solution of 'X' in water is widely used as a preservative. Identify the compound 'X' and write its structure.

Compare its pH nature with a mineral acid.

'X' on reacting with alcohols produces sweet smelling compounds, used in making perfumes. Name the reaction and write its chemical equation.

When sodium carbonate is added to 'X', a colourless gas is produced which turns lime water milky. Write the chemical equation for the reaction giving the name of the salt produced.

Differentiate between saturated and unsaturated hydrocarbons by giving one example each, with a structural formula.

Write the method of converting an unsaturated hydrocarbon into a saturated hydrocarbon. Name the industry where this reaction is commonly used.

Write the name and structure of a hydrocarbon having double bond and four carbon atoms in its one molecule.