Chlorine reacts with saturated hydrocarbons at room temperature in the :

An organic compound $'A'$ has a molecular formula $C_{2}H_{6}O$. $'A'$ on oxidation gives compound $'B'$,which produces effervescence with baking soda.
$(i)$ Identify $'A'$ and $'B'$.
$(ii)$ Write the chemical reaction of $'B'$ with baking soda.

Write true or false for the following statement:
Two pairs of electrons are shared between two nitrogen atoms to form a nitrogen molecule.

What is the role of the metal or reagents written on the arrows in the given chemical reactions?
$(a)$
$(b)$ $CH_{3}COOH + CH_{3}CH_{2}OH \xrightarrow{Conc. H_{2}SO_{4}} CH_{3}COOC_{2}H_{5} + H_{2}O$
$(c)$ $CH_{3}CH_{2}OH \xrightarrow[Heat]{Alkaline KMnO_{4}} CH_{3}COOH$

Explain the given reactions with examples:
$(a)$ Saponification reaction
$(b)$ Combustion reaction

Which of the following functional groups requires a minimum of three carbon atoms to form a stable compound?