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 $..... \ mL$

Which would decrease the $pH$ of $25 \ cm^3$ of a $0.01 \ M$ solution of hydrochloric acid?

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

The $pH$ of a $H_2SO_4$ solution is $5.0$. If more $H_2SO_4$ is added to this solution,the $pH$ becomes $2.0$. The concentration of $H^{+}$ ions will become how many times the initial concentration?

$200 \ mL$ of $0.01 \ M \ HCl$ is mixed with $400 \ mL$ of $0.01 \ M \ H_{2}SO_{4}$. The $pH$ of the mixture is

By adding $20 \ mL$ of $0.1 \ N \ HCl$ to $20 \ mL$ of $0.001 \ N \ KOH$,the $pH$ of the resulting solution will be: