Which of the following compounds are partially soluble or insoluble in $NH_4OH$ solution?
$(I)$ $Fe(OH)_3$
$(II)$ $Ag_2CrO_4$
$(III)$ $Al(OH)_3$
$(IV)$ $Ag_2CO_3$

Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$BaCO_3 \downarrow + 2HCl \longrightarrow BaCl_2 + CO_2 \uparrow + H_2O$

The solubility product of a sparingly soluble salt $A_{2}X_{3}$ is $1.1 \times 10^{-23}$. If specific conductance of the solution is $3 \times 10^{-5} \ S \ m^{-1}$,the limiting molar conductivity of the solution is $x \times 10^{-3} \ S \ m^{2} \ mol^{-1}$. The value of $x$ is ...

What is the $[OH^-]$ in the final solution prepared by mixing $20.0 \ mL$ of $0.050 \ M \ HCl$ with $30.0 \ mL$ of $0.10 \ M \ Ba(OH)_2$?

Equal volumes of aqueous solution of $0.1 \ M \ HCl$ and $0.2 \ M \ H_2SO_4$ are mixed. The concentration of $H^{+}$ ions in the resulting solution is (in $M$)

$CrO_4^{2-}$ (Yellow) changes to $Cr_2O_7^{2-}$ (orange) in $pH = x$ and vice versa in $pH = y$,hence $x$ and $y$ are respectively