The density of $3 \ m$ solution of $NaOH$ is $1.110 \ g \ mL^{-1}$. Calculate the molarity of the solution. (in $M$)

You are supplied with $500 \ mL$ each of $2 \ N \ HCl$ and $5 \ N \ HCl$. What is the maximum volume of $3 \ M \ HCl$ that you can prepare using only these two solutions (in $mL$)?

Molality of an aqueous solution of urea is $4.44 \ m$. Mole fraction of urea in solution is $x \times 10^{-5}$. Value of $x$ is. . . . . . (integer answer)

$A$ sample of drinking water was found to be severely contaminated with chloroform $(CHCl_{3})$,supposed to be a carcinogen. 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.

If $5.85 \ g$ of $NaCl$ is dissolved in $90 \ g$ of water,then find out the mole fraction of $NaCl$.

The molality of $648 \ g$ of pure water is .................. $m$.