The $pH$ of $10^{-7} \ N \ HCl$ is

How many liters of water must be added to $1 \ L$ of an aqueous $HCl$ solution with $pH = 1$ to make the $pH$ of the resulting solution equal to $2$ (in $L$)?

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?

What is the $pH$ of $0.02 \ M \ NaOH$ solution?

$200 \ mL$ of an aqueous solution of $HCl$ $(pH=2)$ is mixed with $300 \ mL$ of aqueous solution of $NaOH$ $(pH=12)$ and is diluted to $1.0 \ L$. The $pH$ of the resulting solution is

Which of the following solutions will have the maximum $pH$?