What is the molarity of a solution containing $3.2 \ g$ of $NaOH$ (molar mass $40 \ g \ mol^{-1}$) in $250 \ cm^{3}$ of water?

The amount of ammonium sulphate required for the preparation of $1 \, M$ solution in $2 \, L$ is ............ $gm$.

What is the physical state of a solution containing camphor as the solute and $N_2$ gas as the solvent?

The molality of a solution is defined as:

$10 \ g$ of $NaOH$ is dissolved in $500 \ mL$ of aqueous solution. Calculate the molarity of this solution? (Given,formula weight of $NaOH = 40$)

$A$ sample of drinking water is found to be severely contaminated with chloroform $(CHCl_3)$,which is a suspected carcinogen. The level of contamination is $15 \ ppm$ (by mass). Calculate the molarity of chloroform in the water sample.