Conc. $H_2SO_4$ has a density of $1.98 \ g/mL$ and is $98\%$ $H_2SO_4$ by weight. Its normality is ......... $N$.

When $100 \ mL$ of $2 \ M \ KCl$ and $200 \ mL$ of $3 \ M \ K_2SO_4$ solutions are mixed,what will be the molarity of $K^+$ ions in the resulting mixture (in $M$)?

If the density of a $2.05 \ M$ $CH_3COOH$ solution is $1.02 \ g/mL$,what is the molality of the solution?

$100 \ mL$ of $\frac{M}{10} \ Ca(NO_3)_2$ and $200 \ mL$ of $\frac{M}{10} \ KNO_3$ solutions are mixed. What is the normality of the resulting solution with respect to $NO_3^{-}$ ions (in $N$)?

$20 \, mL$ of $0.5 \, M \, HCl$ is mixed with $30 \, mL$ of $0.3 \, M \, HCl$. The molarity of the resulting solution is $......... \, M$.

What volume of water is to be added to $50 \, mL$ of $4 \, N$ $NaOH$ solution to obtain a $1 \, N$ solution? $(... \, mL)$