Question

The reaction conditions leading to the best yield of ${C_2}{H_5}Cl$ are:
A) $\,{C_2}{H_6}\left( {excess} \right) + C{l_2} \to \,$
B) $\,{C_2}{H_6} + C{l_2} \to \,$
C) $\,{C_2}{H_6} + C{l_2}\left( {excess} \right) \to \,$
D) None of these

Answer 1

Halogenation of an alkane produces a hydrocarbon derivative during which one or more halogen atoms are substituted for hydrogen atoms. Alkanes are known as notoriously unreactive compounds because they are non-polar and lack functional groups at which reactions can occur. Atom halogenation, therefore, provides a way by which alkanes will be functionalized.

Complete step by step answer:
Alkane halogenation is an example of a substitution reaction, a kind of reaction that usually occurs in the field of chemistry.
Halogenation of alkanes will cause the formation of a Haloalkane.
During this reaction, if we use chlorine in excess, then dichloro and trichloro forms as a product and if ethane is employed in excess, ethyl chloride will be formed as a major product.
So, the reaction takes place as follows:

${C_2}{H_6}(excess) + C{l_2} \to {C_2}{H_5}Cl + HCl\,$

The reaction does not stop at this step, however, because the chlorinated ethane product can react with the additional chlorine to produce polychlorinated products.
A severe limitation of the radical halogenation however is the number of similar $C - H$ bonds that are present in all but the simplest alkanes, so selective reactions are difficult to achieve.

So, the correct answer is Option A .

Note: A substitution reaction may be a reaction within which a part of a tiny low reacting molecule replaces an atom or a gaggle of atoms on a hydrocarbon or hydrocarbon derivative.The notation $R - H$ could be a general formula for an alkane. $R$ during this case represents a radical. The addition of an atom to a group produces the parent hydrocarbon of the alkyl. The notation $R - X$ on the merchandise side is that the general formula for a halogenated alkane. $X$ is the general symbol for a halogen atom. Reaction conditions are noted by placing these conditions on the equation arrow that separates reactants from products. Halogenation of an alkane requires the presence of warmth or light.