The concentration in $M$ of $OH^{-}$ in $0.001 \ M$ $H_2SO_4$ is

The $pH$ of a $10 \ mL$ aqueous solution of $HCl$ is $4$. The amount of water to be added to this solution in order to change its $pH$ from $4$ to $5$ is $..... \ mL$

$x \ mg$ of $Mg(OH)_2$ (molar mass $= 58 \ g/mol$) is required to be dissolved in $1.0 \ L$ of water to produce a $pH$ of $10.0$ at $298 \ K$. The value of $x$ is $........... mg$ ($Nearest$ $integer$). ($Given$: $Mg(OH)_2$ is assumed to dissociate completely in $H_2O$)

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

If $100 \, mL$ of a solution with $pH = 3$ is mixed with $400 \, mL$ of another solution with $pH = 3$,what will be the $pH$ of the resulting mixture?

The highest $pH$ $(14)$ will be of which of the following?