Melittin present in the bite of honeybee is a polypeptide containing $......$ amino acids.

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

Carbon exists in the atmosphere in the form of

The high temperature resistance property of $Neoprene$ is due to the presence of a large number of which atom?

$(i)$ Give one example with a chemical equation for the following reactions:
$(a)$ Substitution reaction.
$(b)$ Saponification reaction.
$(c)$ Combustion reaction.

Write the balanced chemical equations for the following reactions and identify the type of reaction in each case.
$(a)$ Ethanol is warmed with ethanoic acid to form ethyl acetate in the presence of concentrated $H_2SO_4$.
$(b)$ Ethene is burnt in the presence of oxygen to form carbon dioxide, water and releases heat and light.