Question

Lucas reagent is.
A)$Con\,HCl\,and\,anhydrous\,ZnC{l_2}$
B)$Con\,HCl\,and\,hydrous\,ZnC{l_2}$
C)$Con\,HN{O_3}\,and\,hydrous\,ZnC{l_2}$
D) $Con\,HN{O_3}\,and\,anhydrous\,ZnC{l_2}$

Answer 1

We know Lucas reagent is a solution of a transition metal chloride in inorganic acid. This solution is employed to identify the alcohols of low relative molecular mass. A positive test is indicated by a change from clear and colorless to the turbid solution.

Complete step by step answer:

We must remember that the Lucas reagent is the solution of concentrated hydrochloric acid with anhydrous zinc chloride. Both concentrated hydrochloric acid and zinc chloride are taken in the same molarities to make the reagent.
Therefore, the option A is correct.
Lucas Test:
Lucas reagent reacts with alcohol and gives different results based on the stability of the carbocation intermediate formed during the reaction. Chloride ion of hydrochloric acid reacts with an alkyl group of alcohol and forms alkyl chloride on the other hand Zinc chloride is used as a catalyst. The rate of the reaction differs from the nature of alcohol. Primary, secondary, and tertiary alcohols give different bases with the Lucas reagent.

Therefore the option A is correct.

Additional Information:
Carbocation:
An ion in which the carbon carries a positive charge is called carbocation and they are formed by the heterolytic cleavage.
Stability of the carbocation:
The stability of the allylic carbocation depends on the inductive effect of the alkyl group attached to the carbocation. The stability of the carbocation increases with an increase in the number of alkyl groups.
The stability order of carbocation is,
${{\text{3}}^{\text{o}}}{\text{ > }}{{\text{2}}^{\text{o}}}{\text{ > }}{{\text{1}}^{\text{o}}}$

Note:
We must remember that the salts which do not have water molecules are called anhydrous salt. Copper sulfate has a water molecule that is on heating, loses its water molecules and gives anhydrous copper sulfate.