Question

In Victor Meyer’s Test, which compound do we get for primary alcohol?
(a) Nitrolic Acid
(b) Nitroalkane
(c) Pseudo Nitrol
(d) None of these

Answer 1

Hint: As we know, Victor’s Meyer’s Test is an important test for the distinction of alcohols. It is an organic compound with functional group $\text{RC(N}{\text{O}}_2)=\text{NOH}$ and is red in color.

Complete step by step answer:
First let us discuss the application of Victor Meyer’s Test.
Victor Meyer’s Test is one of the prominent tests to distinguish between primary, secondary and tertiary alcohol. In this test, the unknown alcohol is subjected to a series of chemical analysis resulting in observation of colour. Different colours are observed for different alcohols.
The different steps involved in Victor Meyer’s methods for distinction of different types of alcohol are as mentioned below:
The alcohol is treated with iodine in presence of red phosphorus to obtain iodoalkane.
Iodoalkane so formed is allowed to react with alcoholic silver nitrate in order to obtain nitroalkane.
The nitroalkane is treated with nitrous acid (mixture of $\text{NaN}{\text{O}}_2$ and$\text{HCl}$) and the resulting solution is made alkaline by the addition of Caustic Soda.
The colour of the resulting solution is observed in which following observations are made.
The primary alcohol gives blood red colour.
The secondary alcohol gives the blue colour.
And the tertiary alcohol does not produce any colour.
The reaction involved is:
$$\text{RC}{\text{H}}_2\text{OH+HI}\to \text{RC}{\text{H}}_2\text{I}$$
$$\text{RC}{\text{H}}_2\text{I+AgN}{\text{O}}_2\to \text{RC}{\text{H}}_2\text{N}{\text{O}}_2$$
$$\text{RC}{\text{H}}_2\text{N}{\text{O}}_2+\text{HN}{\text{O}}_2\to \text{R-C-N}{\text{O}}_2(\text{NOH)}$$(Blood red colour)
The final compound that formed is called Nitrolic acid and therefore, the correct option is (a) Nitrolic Acid.

Note: When the above reagents react with secondary alcohol, the final product obtained is called pseudo nitrile. With tertiary alcohol, there is no reaction. It is also known as the Red, blue and White test.