What is the $pH$ of a $NaOH$ solution with a concentration of $0.01 \ g \ L^{-1}$?

$40 \, mg$ of pure sodium hydroxide is dissolved in $10 \, L$ of distilled water. The $pH$ of the solution is

$50 \, mL$ water is added to a $50 \, mL$ solution of $Ba(OH)_2$ of strength $0.01 \, M$. The $pH$ value of the resulting solution will be

What will be the concentration of $H^{+}$ ions in a solution prepared by dissolving $4 \ g$ of $NaOH$ in $100 \ mL$ of water at $25 \ ^{\circ}C$?

$50 \ mL$ of water is added to $50 \ mL$ of $0.01 \ M$ $Ba(OH)_2$ solution. Calculate the $pH$ of the resulting solution.

Assuming that $Ba(OH)_{2}$ is completely ionised in aqueous solution under the given conditions,the concentration of $H_{3}O^{+}$ ions in $0.005 \, M$ aqueous solution of $Ba(OH)_{2}$ at $298 \, K$ is $..... \times 10^{-12} \, mol \, L^{-1}$. (Nearest integer)