# Question 3b50a

Mar 17, 2016

See explanation.

#### Explanation:

You're essentially dealing with four ionic compounds that are insoluble in aqueous solution.

Silver chloride, $\text{AgCl}$, is a white precipitate that can be obtained by mixing a solution of a soluble ionic compound that contains the silver(I) cation, ${\text{Ag}}^{+}$, with a solution of a soluble ionic compound that contains the chloride anion, ${\text{Cl}}^{-}$.

Lead(II) chromate, ${\text{PbCrO}}_{4}$, is a yellow precipitate that can be obtained by mixing a solution of a soluble ionic compound that contains the lead(II) cation, ${\text{Pb}}^{2 +}$, with a solution of a soluble ionic compound that contains the chromate anion, ${\text{CrO}}_{4}^{2 -}$.

Copper(II) sulfide, $\text{CuS}$, is a black precipitate that can be formed by mixing a solution of a soluble ionic compound that contains the copper(II) cation, ${\text{Cu}}^{2 +}$, with a solution of a soluble ionic compound that contains the sulfide anion, ${\text{S}}^{2 -}$.

Finally, nickel(II) hydroxide, "Ni"("OH")_2#, is a green precipitate that results when a solution of a soluble ionic compound that contains the nickel(II) cation, ${\text{Ni}}^{2 +}$, is mixed with a solution of a soluble ionic compound that contains the hydroxide anion, ${\text{OH}}^{-}$.