Action of Ammonium Hydroxide on Metallic Salt Solutions

Consider following sequence of chemical reactions that have been carried out in laboratory.

(i) Unknown salt '$\mathrm{A}$' $+{\mathrm{Na}}_2{\mathrm{CO}}_3\left(\mathrm{s}\right)+$ Distilled water $\underset{\mathrm{filtre}}{\overset{\mathrm{Boil} \mathrm{and}}{\to }}\underset{\mathrm{ppt}}{B}\downarrow +C$

(ii) '$\mathrm{C}$'$+{\mathrm{Cr}}_2{\mathrm{O}}_7{}^{2-}\left(\mathrm{aq}\right)+{\mathrm{H}}^{+}\left(\mathrm{aq}\right)⟶$ Colour of ${\mathrm{Cr}}_2{\mathrm{O}}_7^{2-}$ remains same (No reaction)

(iii) $\mathrm{B}\downarrow +$ dil. $\mathrm{HCl}⟶$ Coloured solution $\stackrel{{\mathrm{NH}}_4\mathrm{Cl}+{\mathrm{NH}}_4\mathrm{OHsol}.}{\to }\underset{\left(\mathrm{precipitate}\right)}{D\downarrow }$

Then the unknown salt '$\mathrm{A}$' is:

What will be the action of sodium hydroxide on ammonium salt?

 ${\mathrm{Al}}^{3+}$ salts react with ammonium hydroxide in presence of ammonium chloride to give a black precipitate of aluminium chloride. 

What will be the colour of the precipitate formed when  $\mathrm{Al}\left(\mathrm{III}\right)$ ions react with ammonium hydroxide in presence of ammonium chloride. 

Write the chemical equation for the reaction of $\mathrm{Al}\left(\mathrm{III}\right)$ ions with ammonium hydroxide in presence of ammonium chloride. 

What happens when $\mathrm{Al}\left(\mathrm{III}\right)$ ions react with ammonium hydroxide in presence of ammonium chloride. 

The colour of the precipitate formed in the reaction of $\mathrm{Cr}\left(\mathrm{III}\right)$ ions with ammonium hydroxide in presence of ammonium chloride is

An aqueous solution of $\mathrm{Cr}\left(\mathrm{III}\right)$ ions react with ammonium hydroxide in presence of ammonium chloride to give a reddish-brown precipitate. 

What will be the products formed in the reaction of $\mathrm{Cr}\left(\mathrm{III}\right)$ ions with ammonium hydroxide. 

Write a chemical equation for the action of ammonium hydroxide on $\mathrm{Cr}\left(\mathrm{III}\right)$ ions.

What do you observe when an ammonium salt is heated with caustic soda solution? 

Ammonium hydroxide reacts to distinguish $\mathrm{F}\mathrm{e}\mathrm{C}{\mathrm{l}}_2$ solution from $\mathrm{F}\mathrm{e}\mathrm{C}{\mathrm{l}}_3$ solution.

The addition of an excess of ammonium chloride ammonia buffer to a solution containing nitrates of $\mathrm{Al}, \mathrm{Bi}, \mathrm{Mg}$ and $\mathrm{Zn}$ will precipitate hydroxides of

A compound is soluble in water. If ammonia is added, a red precipitate appears which is soluble in dilute $\mathrm{HCl}$. The compound has

The reagents $N{H}_{4}Cl$ and aqueous $N{H}_3$ will precipitate

$A{l}^{3+},$ $F{e}^{3+},$ $Z{n}^{2+}$ and $N{i}^{2+}$ ions are present in an acidic solution. Excess of ammonium chloride solution is added followed by addition of ammonium hydroxide solution. The available precipitate will contain

To avoid the precipitation of hydroxides of ${\mathrm{Ni}}^{2+}, {\mathrm{Co}}^{2+}, {\mathrm{Zn}}^{2+}$ and ${\mathrm{Mn}}^{2+}$ along with those of ${\mathrm{Fe}}^{3+}, {\mathrm{Al}}^{3+}$ and ${\mathrm{Cr}}^{3+}$, the third group solution should be