If $0.1 \, M, 100 \, mL$ $NaOH$ solution is mixed with $0.05 \, M, 100 \, mL$ $H_2SO_4$ solution,the $pH$ of the resulting solution is:

The molar conductivity of $0.01 \text{ M}$ monobasic acid at $25 \text{ }^\circ\text{C}$ is $15 \text{ ohm}^{-1} \text{cm}^2 \text{mol}^{-1}$. The molar conductivity of the same acid at infinite dilution is $375 \text{ ohm}^{-1} \text{cm}^2 \text{mol}^{-1}$. Calculate $[H^+]$ in solution.

Which of the following pairs of substances cannot exist together in a solution?

$A$ certain amount of $H_2CO_3$ and $HCl$ are dissolved to form $1 \ L$ solution. At equilibrium,it is found that the concentrations of $H_2CO_3$ and $CO_3^{2-}$ are $0.1 \ M$ and $0.01 \ M$ respectively. Calculate the $pH$ of the solution. Given that for $H_2CO_3$,$K_{a_1} = 10^{-5}$ and $K_{a_2} = 10^{-8}$.

$30 \ cc$ of $\frac{M}{3} \ HCl$,$20 \ cc$ of $\frac{M}{2} \ HNO_{3}$ and $40 \ cc$ of $\frac{M}{4} \ NaOH$ solutions are mixed and the volume was made up to $1 \ dm^{3}$. The $pH$ of the resulting solution is

The number of hydroxyl ions in $10 \text{ cm}^3$ of $0.2 \text{ M}$ $HCl$ solution is