$100 \ mL$ 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 $N$)?

Calculate the mass of Glucose $(C_6H_{12}O_6)$ required in making $2.5 \ kg$ of $0.25 \ molal$ aqueous solution. [Atomic wt : $H=1, O=16, C=12 \ amu$] (in $g$)

$A$ certain aqueous solution of $FeCl_3$ (formula mass $= 162 \ g/mol$) has a density of $1.1 \ g/mL$ and contains $20.0 \ \% \ FeCl_3$ by mass. The molar concentration (molarity) of this solution is: (in $M$)

Two solutions labeled as $3\,M\,HCl$ and $1\,M\,HCl$ are mixed in the ratio of $x : y$ by volume and the molarity of the resulting solution is $1.5\,M$. The molarity of the resulting solution if they are mixed in the ratio $y : x$ by volume is ....... $M$.

If a $3.6 \, M$ solution of $H_2SO_4$ contains $29 \% \, H_2SO_4$ by mass,find the density of the $H_2SO_4$ solution. (Molar mass of $H_2SO_4 = 98 \, g \, mol^{-1}$)

$A$ sample of drinking water is severely contaminated with chloroform $(CHCl_3)$. $CHCl_3$ is considered carcinogenic in nature. The level of contamination was $15 \ ppm$ (by mass).
$(i)$ Express this in percent by mass.
$(ii)$ Determine the molality of chloroform in the water sample.