Give a chemical test to distinguish between the calcium nitrate and zinc nitrate solutions.

Classify the following metal salts, whose precipitate is formed by the action of $\mathrm{NaOH}$ which is soluble and insoluble in excess of $\mathrm{NaOH}$ solution.

$\mathrm{C}\mathrm{a}{\left(\mathrm{N}{\mathrm{O}}_3\right)}_2, \mathrm{F}\mathrm{e}\mathrm{S}{\mathrm{O}}_4, \mathrm{C}\mathrm{u}\mathrm{S}{\mathrm{O}}_4, \mathrm{Z}\mathrm{n}\mathrm{S}{\mathrm{O}}_4, \mathrm{P}\mathrm{b}{\left(\mathrm{N}{\mathrm{O}}_3\right)}_2$

Name the metal salt which is soluble in ammonium hydroxide. 

Complete the following reaction. 

${\text{Zn(OH)}}_2\text{+}{\left({\text{NH}}_4\right)}_{\text{2}}{\text{SO}}_{\text{4}}{\text{+2NH}}_4{\text{OH→ \_\_\_\_\_ +4H}}_2\text{O}$