What is the $pH$ of the resulting solution when equal volumes of $0.1 \ M \ NaOH$ and $0.01 \ M \ HCl$ are mixed?

Equal volumes of three acid solutions of $pH$ $3$,$4$ and $5$ are mixed in a vessel. What will be the $H^{+}$ ion concentration in the mixture in terms of $\times 10^{-4} \ M$?

Which of the following solutions will have $pH$ close to $1.0$?

Given $pH$ of a solution $A$ is $3$ and it is mixed with another solution $B$ having $pH$ $2$. If both are mixed in equal volumes,then the resultant $pH$ of the solution will be

$pH$ of a $10 \ M$ solution of $HCl$ is

$4 \ g$ of $NaOH$ is added in water to form $500 \ mL$ solution at $298 \ K$. What is the $pH$ of the solution? (Molar mass of $NaOH = 40 \ g \ mol^{-1}$)