Give an example to show the effect of concentration of nitric acid on the formation of oxidation product.
Effect of concentration of nitric acid on the formation of oxidation product can be understood by its reaction with conc $\mathrm{HNO}_3$. Dilute and concentrated nitric acid give different oxidation products on reaction with copper metal.
$$\begin{gathered} 3 \mathrm{Cu}+8 \mathrm{HNO}_3 \text { (Dil.) } \longrightarrow 3 \mathrm{Cu}\left(\mathrm{NO}_3\right)_2+2 \mathrm{NO}+4 \mathrm{H}_2 \mathrm{O} \\ \mathrm{Cu}+4 \mathrm{HNO}_3 \text { (Conc.) } \longrightarrow \mathrm{Cu}\left(\mathrm{NO}_3\right)_2+2 \mathrm{NO}_2+2 \mathrm{H}_2 \mathrm{O} \end{gathered}$$
$\mathrm{PCl}_5$ reacts with finely divided silver on heating and a white silver salt is obtained, which dissolves on adding excess aqueous $\mathrm{NH}_3$ solution. Write the reactions involved to explain what happens.
$\mathrm{PCl}_5$ on reaction with finely divided silver produced silver halide.
$$\mathrm{PCl}_5+2 \mathrm{Ag} \longrightarrow 2 \mathrm{AgCl}+\mathrm{PCl}_3$$
AgCl on further reaction with aqueous ammonia solution produces a soluble complex of $\left[\mathrm{Ag}\left(\mathrm{NH}_3\right)_2\right]^{+} \mathrm{Cl}^{-}$
$\mathrm{AgCl}+2 \mathrm{NH}_3(a q) \longrightarrow \underset{\text { Soluble complex }}{\left[\mathrm{Ag}\left(\mathrm{NH}_3\right)_2\right]^{+}} \mathrm{Cl^-}$
Phosphorus forms a number of oxoacids. Out of these oxoacids, phosphinic acid has strong reducing property. Write its structure and also write a reaction showing its reducing behaviour.
Among various forms of oxoacids, phosphinic acid has stronger reducing property.
Reaction showing reducing behaviour of phosphinic acid is as follows
$$4 \mathrm{AgNO}_3+2 \mathrm{H}_2 \mathrm{O}+\mathrm{H}_3 \mathrm{PO}_2 \longrightarrow 4 \mathrm{Ag} \downarrow+4 \mathrm{HNO}_3+\mathrm{H}_3 \mathrm{PO}_4$$
Match the compounds given in Column I with the hybridisation and shape given in Column II and mark the correct option.
| Column I | Column II | ||
|---|---|---|---|
| A. | $\mathrm{XeF_6}$ | 1. | $sp^3d^3$-distorted octahedral |
| B. | $\mathrm{XeO_3}$ | 2. | $sp^3d^2$-square planar |
| C. | $\mathrm{XeOF_4}$ | 3. | $sp^3$-pyramidal |
| D. | $\mathrm{XeF_4}$ | 4. | $sp^3d^2$-square pyramidal |
Match the formulas of oxides given in Column I with the type of oxide given in Column II and mark the correct option.
| Column I | Column II | ||
|---|---|---|---|
| A. | $\mathrm{Pb_3O_4}$ | 1. | Neutral oxide |
| B. | $\mathrm{N_2O}$ | 2. | Acidic oxide |
| C. | $\mathrm{Mn_2O_7}$ | 3. | Basic oxide |
| D. | $\mathrm{Bi_2O_3}$ | 4. | Mixed oxide |