Chemistry - PRACTICAL ORGANIC CHEMISTRY Question with Solution | TestHub

${\mathrm{Na}}_2\mathrm{S}$ and $\mathrm{NaCN},$ formed during fusion with metallic sodium, must be removed before adding ${\mathrm{AgNO}}_3,$ otherwise black ppt. due to ${\mathrm{Na}}_2\mathrm{S}$ or white precipitate due to $\mathrm{AgCN}$ will be formed and thus white precipitate of $\mathrm{AgCl}$ will not be identified easily. ${\mathrm{Na}}_2\mathrm{S}+2{\mathrm{AgNO}}_3⟶2{\mathrm{NaNO}}_3+\underset{\text{ Black }}{{\mathrm{Ag}}_2\mathrm{S}}\downarrow$ $\mathrm{NaCN}+{\mathrm{AgNO}}_3⟶{\mathrm{NaNO}}_3+\underset{\text{ White }}{\mathrm{AgCN}}\downarrow$ $\mathrm{NaCl}+{\mathrm{AgNO}}_3⟶{\mathrm{NaNO}}_3+\underset{\text{ White }}{\mathrm{AgCl}}\downarrow$ ${\mathrm{Na}}_2\mathrm{S}+2{\mathrm{HNO}}_3\stackrel{\text{ boil }}{⟶}2{\mathrm{NaNO}}_3+{\mathrm{H}}_2\mathrm{S}\uparrow$ $\mathrm{NaCN}+{\mathrm{HNO}}_3\stackrel{\text{ boil }}{⟶}{\mathrm{NaNO}}_3+\mathrm{HCN}\uparrow$