What is the $pH$ of a $0.005 \ M$ $Ba(OH)_2$ solution?

Calculate the $pH$ of $1.0 \times 10^{-8} \ M \ NaOH$ solution.

An alkaline solution of $Mg(OH)_2$ has $pH = 12$. What amount of $Mg(OH)_2$ (in $gm$) is dissolved in $200 \ mL$ of the final solution?

$75 \ mL$ of $0.2 \ M \ HCl$ is mixed with $25 \ mL$ of $1 \ M \ HCl$. To this solution,$300 \ mL$ of distilled water is added. What is the $pH$ of the resultant solution?

Which of the following solutions has the highest $pH$?

What is the $pH$ of a solution in which $25.0 \ mL$ of $0.1 \ M \ NaOH$ is added to $25 \ mL$ of $0.08 \ M \ HCl$ and the final solution is diluted to $500 \ mL$?