Question

Color of Primary Alcohol in Victor Mayer’s Test is:
a.) Blue
b.) Red
c.) Green
d.) No color

Answer 1

Hint: Victor Meyer’s test is used to distinguish between different kinds of alcohol. On subjecting primary, secondary and tertiary alcohols to the same set of chemical reactions, they give various results thus helping us to distinguish between them.

Complete step by step answer:
Let us first have a look at the reactions involved in this Victor Meyer’s Test.
Firstly, the alcohol sample given to us is treated with iodine in presence of red phosphorus to form the corresponding iodoalkane.
This iodoalkane is then made to react with alcoholic silver nitrate solution in order to get nitroalkane.
This nitroalkane is then treated with nitrous acid (which is nothing but a mixture of sodium nitrate and hydrochloric acid). The solution we get is then made alkaline.
We would then observe the color of this resulting solution and base our conclusion on this.
We would see that a primary alcohol produces a blood red color; blue colored solution is obtained from a secondary alcohol while a tertiary alcohol produces no color on undergoing this process.

Hence, the correct answer is Option (B) Red.

Additional information:
Phenol does not give Victor Meyer Test as phenol has much stronger carbon-oxygen bond than aliphatic alcohols and cannot undergo substitution reaction.

Note:
We must remember that the red color found in primary alcohol is due to the production of Nitrolic acid and the blue color of secondary alcohol is by virtue of pseudo nitrol. Since no reaction occurs with tertiary alcohol, no coloration is observed.