Question

Identify the reagents X, Y, Z for the following products:

a.) X= ${ I }_{ 2 }$ warm, Y= KCN, warm, Z= NaOH, warm
b.) X= CuI, Y= NaCN, Z= KOH
c.) X= KI,warm, Y= CuCN, Z= ${ H }_{ 2 }O$,warm
d.) X=AgI,warm, Y=AgCN,warm, Z= KOH,boil

Answer 1

Hint: Try to recall the chemical composition of benzene diazonium chloride. Then only you can figure out why this compound is unstable and what it will form after decomposition.

Complete step by step answer:

First, let’s gain some knowledge about the species Benzenediazonium chloride.
This compound is prepared by the diazotization of aniline in the presence of hydrochloric acid. The conversion involves in situ production of nitrous acid ($HNO_{ 2 }$), which reacts with the aniline:
$C_{ 6 }H_{ 5 }NH_{ 2 }\quad +\quad HNO_{ 2 }\quad +\quad HCl\quad \rightarrow \quad [C_{ 6 }H_{ 5 }N_{ 2 }]Cl\quad +\quad 2H_{ 2 }O$
The reactions are conducted at low temperatures to minimize the decomposition of the diazonium salt. The diazonium salt is not isolated.
It is a water-soluble compound when it is at high temperature and can easily be soluble in water which explains the unstable nature. Therefore, after its preparation it was cooled down to below 5-degree centigrade and then it is stored at that temperature itself.
Benzene diazonium chloride cannot be stored and is used immediately after its preparation because of this unstable nature and with a slight increase in temperature, it dissociates to give nitrogen.

Therefore, we can conclude that option B is correct.

Note: Benzene diazonium chloride is an organic compound with the formula $ [C_{ 6 }H_{ 5 }N_{ 2 }]Cl$. It is a salt of a diazonium cation and chloride. It exists as a colorless solid that is soluble in polar solvents including water. It is the parent member of the aryl diazonium compounds, which are widely used in organic chemistry. Because the salt is unstable, it is not commercially available but is prepared upon demand.