v. M saturated solution of [Cd(NH_(3))_(4)]Cl_(2) 6. Suggest a scheme for analyzing a solution containing the following ions: Pb^2+;Hg_(2)^2+;NO_(3)^- . What is the color of the solution? Write the equations of analytical reactions.

To analyze a solution containing the ions $Pb^{2+}$, $Hg_{2}^{2+}$, and $NO_{3}^{-}$, we can use a combination of precipitation and complexation reactions. Here is a suggested scheme:<br /><br />1. **Precipitation of $Pb^{2+}$:**<br /> - Add a few drops of ammonium hydroxide (NH$_3$) solution to the solution. This will precipitate $Pb^{2+}$ as $Pb(OH)_2$.<br /> - **Equation:** $Pb^{2+} + 2NH_3 + 2H_2O \rightarrow Pb(OH)_2 + 2NH_4^+$<br /><br />2. **Precipitation of $Hg_{2}^{2+}$:**<br /> - After the $Pb(OH)_2$ precipitate has formed, add more ammonium hydroxide to the solution. This will precipitate $Hg_{2}^{2+}$ as $Hg(OH)_2$.<br /> - **Equation:** $Hg_{2}^{2+} + 4NH_3 + 6H_2O \rightarrow 2Hg(OH)_2 + 4NH_4^+$<br /><br />3. **Detection of $NO_{3}^{-}$:**<br /> - The remaining solution should contain $NO_{3}^{-}$. To confirm the presence of $NO_{3}^{-}$, add a few drops of silver nitrate (AgNO$_3$) solution. A white precipitate of $AgCl$ will form if $Cl^-$ is present.<br /> - **Equation:** $Ag^+ + Cl^- \rightarrow AgCl(s)$<br /><br />**Color of the Solution:**<br />- The solution will initially be colorless. After the formation of $Pb(OH)_2$ and $Hg(OH)_2$ precipitates, the solution may appear slightly cloudy due to the presence of these precipitates.<br /><br />**Summary of Analytical Reactions:**<br />1. $Pb^{2+} + 2NH_3 + 2H_2O \rightarrow Pb(OH)_2 + 2NH_4^+$<br />2. $Hg_{2}^{2+} + 4NH_3 + 6H_2O \rightarrow 2Hg(OH)_2 + 4NH_4^+$<br />3. $Ag^+ + Cl^- \rightarrow AgCl(s)$<br /><br />This scheme allows for the identification and differentiation of the ions $Pb^{2+}$, $Hg_{2}^{2+}$, and $NO_{3}^{-}$ through a combination of precipitation and complexation reactions.