An unknown inorganic compound (X ) gave the following reactions.
(i) The compound (X ) on heating gas a residue, oxygen and oxide of nitrogen.
(ii) An aqueous solution of compound (X) on addition to tap water gas a turbidity which did not dissolve in `HNO_(3)`.
(iii) The turbidity dissolved in `NH_(4)OH`.
Identify the compound (X) and give equations for the reactions (i),(ii) & (iii).

Explanation

(I) Step (ii) suggest X to be a compound of Ag as it gives tubidity with tab water which contains `Cl^(-)`. Since the turbidity is soluble in `NH_(4)OH`.
(II) X may be `AgNO_(3)` since it gives oxides of Nitrogen.
Reactions `: 2 AgNO_(3) rarr underset("residue")(2Ag)+2NO_(2)+O_(2)`
`AgNO_(3)+Cl^(-) rarr underset((X) "tap water Turbidity")(AgCl)+NO_(3)^(-)`
`AgCl+2NH_(4)Oh rarr underset("soluble")(Ag(NH_(3))_(2)Cl)+2H_(2)O`