CAIE A-Level Chemistry A2 34.2.2 Describe Topic Practice

Potassium iodide, KI, is used as a reagent in both inorganic and organic chemistry.

$\quad \mathrm{KI}$ is used as a source of $\mathrm{I}^{-}$ions in organic synthesis.

One example of this is shown in the synthetic route in Fig. 1.1.

Step 3 occurs in two stages.
stage I $\mathrm{NaNO}_{2}$ and HCl undergo an acid-base reaction to produce $\mathrm{HNO}_{2}$.
stage II $\mathrm{HNO}_{2}$ reacts with $\mathbf{C}, \mathrm{C}_{6} \mathrm{H}_{5} \mathrm{NH}_{2}$, to produce $\mathbf{D}, \mathrm{C}_{6} \mathrm{H}_{5} \mathrm{~N}_{2}{ }^{+}$.
Complete the equations for stage I and for stage II.

stage I $\mathrm{NaNO}_{2}+\mathrm{HCl} \rightarrow$

stage II