$HCl$ gas was passed through a solution containing $CaCl_{2}$,$MgCl_{2}$,and $NaCl$. Which of the following compound$(s)$ crystallise$(s)$?

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: $\lambda^{\circ}_{(Ag^{+})} = 6 \times 10^{-3} \ S \ m^2 \ mol^{-1}$,$\lambda^{\circ}_{(Br^{-})} = 8 \times 10^{-3} \ S \ m^2 \ mol^{-1}$,$\lambda^{\circ}_{(NO_3^-)} = 7 \times 10^{-3} \ S \ m^2 \ mol^{-1}$.

On addition of ammonium chloride to a solution of ammonium hydroxide,what happens to the concentration of $OH^{-}$ ions?

On passing $HCl$ gas in a saturated solution of $NaCl$,the solubility of $NaCl$

Given below are two statements:
Statement $I$: On passing $HCl_{(g)}$ through a saturated solution of $BaCl_2$,at room temperature white turbidity appears.
Statement $II$: When $HCl$ gas is passed through a saturated solution of $NaCl$,sodium chloride is precipitated due to common ion effect.
In the light of the above statements,choose the most appropriate answer from the options given below:

$H_2S$ will precipitate the sulphides of all the metals from the solution of chlorides of $Cu, Zn$ and $Cd,$ if