What is the $pH$ value for $\frac{N}{10} \ H_2SO_4$?

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?

What will be the $H^{+}$ ion concentration when $4 \ g$ $NaOH$ is dissolved in $1000 \ mL$ solution?

The hydroxyl ion concentration of $10^{-2} \ M \ HCl$ is:

$75 \ mL$ 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?

What is the $pH$ of a centimolar solution of $H_2SO_4$?