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

The $pH$ value of $0.1 \, M \, HCl$ is approximately $1$. What will be the approximate $pH$ value of $0.05 \, M \, H_2SO_4$?

Five solutions of $KOH$ are prepared as follows: $1st \to 0.1 \ mol$ in $1 \ L$,$2nd \to 0.2 \ mol$ in $2 \ L$,$3rd \to 0.3 \ mol$ in $3 \ L$,$4th \to 0.4 \ mol$ in $4 \ L$,$5th \to 0.5 \ mol$ in $5 \ L$. What is the $pH$ of the resulting mixture?

What is the concentration of hydrogen $[H^{+}]$ ions in $0.01 \, M \, HCl$?

$L$ litres of water must be added to $1 \, L$ of an aqueous solution of $HCl$ with a $pH$ of $1$ to create an aqueous solution with $pH$ of $2$?

When $50 \, mL$ of $0.4 \, N$ $HCl$ and $50 \, mL$ of $0.2 \, N$ $NaOH$ solutions are mixed,the $pH$ of the resulting solution will be ........