question_answer

In the Victor-Meyer's test, the colour given by \[1{}^\circ ,\text{ }2{}^\circ \text{ }and\text{ }3{}^\circ \] alcohols are respectively:   [JEE Main Online Paper ( Held On 12 Apirl  2014 )

A) Red, colourless, blue

B) Red, blue, colourless

C) Colourless, red, blue

D) Red, blue, violet

Correct Answer: B

Solution :

victor Meyer's test: The various steps involved are (i) \[RC{{H}_{2}}OH\xrightarrow[{}]{HI}RC{{H}_{2}}I\xrightarrow[{}]{AgN{{O}_{2}}}RC{{H}_{2}}N{{O}_{2}}\xrightarrow[{}]{HN{{O}_{2}}}\]\[R-\underset{Nitrolic\,acid}{\mathop{\underset{\begin{smallmatrix}  || \\  NOH \end{smallmatrix}}{\mathop{C}}\,}}\,-N{{O}_{2}}\xrightarrow[{}]{KOH}\] (ii) \[RCHOHR\xrightarrow[{}]{HI}_{R}^{R}>CHI\xrightarrow[{}]{AgN{{O}_{2}}}_{R}^{R}>CHN{{O}_{2}}\] (iii) \[{{R}_{3}}COH\xrightarrow[{}]{HI}{{R}_{3}}CI\xrightarrow[{}]{AgN{{O}_{2}}}{{R}_{3}}CN{{O}_{2}}\] \[\xrightarrow[{}]{HN{{O}_{2}}}\]No reaction\[\xrightarrow[{}]{KOH}\]Colourless