The number of moles of hydroxide $(OH^{-})$ ion in $0.3 \ L$ of $0.005 \ M$ solution of $Ba(OH)_2$ is

Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$BaSO_4(s) + Na_2CO_3(aq) \longrightarrow BaCO_3(s) + Na_2SO_4(aq)$

On decreasing the $pH$ from $7$ to $2$,the solubility of a sparingly soluble salt $(MX)$ of a weak acid $(HX)$ increased from $10^{-4} \ mol \ L^{-1}$ to $10^{-3} \ mol \ L^{-1}$. The $pK_{a}$ of $HX$ is:

At $298 \, K$,a $0.1 \, M$ $CH_3COOH$ solution is $1.34 \%$ ionized. The ionization constant $K_a$ for acetic acid will be:

Conductivity of $0.00241 \, M$ acetic acid is $7.896 \times 10^{-5} \, S \, cm^{-1}$. Calculate its molar conductivity. If $\Lambda_m^o$ for acetic acid is $390.5 \, S \, cm^2 \, mol^{-1}$,what is its dissociation constant?

Equal volumes of three acid solutions with $pH$ values of $3, 4,$ and $5$ are mixed. What will be the concentration of $H^+$ ions in the resulting mixture?