The molality (in $mol \ kg^{-1}$) of $1 \ mol$ of solute in $50 \ g$ of solvent is

What is the mole fraction of water in a spirit sample containing $92 \%$ ethyl alcohol by weight?

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

$A$ solution is prepared by adding $2 \ g$ of $X$ to $1 \ mole$ of water. Mass percent of $X$ in the solution is $............. \ \%$

$A$ commercially sold concentrated $HCl$ is $35 \%$ $HCl$ by mass. If the density of this commercial acid is $1.46 \ g/mL$,the molarity of this solution is $....M$.
(Atomic mass : $Cl = 35.5 \ amu, H = 1 \ amu$)

Which of the following concentration factors changes with temperature?