$A$ mixture containing $Cu^{2+}$ and $Ni^{2+}$ can be separated for identification by

We have taken a saturated solution of $AgBr$. The $K_{sp}$ of $AgBr$ is $12 \times 10^{-14}$. If $10^{-7} \ mol$ of $AgNO_3$ are added to $1 \ L$ of this solution,find the conductivity (specific conductance) of this solution in terms of $10^{-7} \ S \ m^{-1}$ units.
Given: $\lambda^{\circ}_{(Ag^{+})} = 6 \times 10^{-3} \ S \ m^2 \ mol^{-1}$,$\lambda^{\circ}_{(Br^{-})} = 8 \times 10^{-3} \ S \ m^2 \ mol^{-1}$,$\lambda^{\circ}_{(NO_3^-)} = 7 \times 10^{-3} \ S \ m^2 \ mol^{-1}$.

$25 \ mL$ of silver nitrate solution $(1 \ M)$ is added dropwise to $25 \ mL$ of potassium iodide $(1.05 \ M)$ solution. The ion$(s)$ present in very small quantity in the solution is/are $........$.

The presence of $NH_4Cl$ in the test solution while precipitating group $III-A$ hydroxides (in qualitative inorganic analysis) helps in:

Addition of which chemical will decrease the hydrogen ion concentration of an acetic acid solution?

The solubility of $AgI$ in $NaI$ solution is less than that in pure water because