Which unit of concentration value does not change with change in temperature?

$A$ mixture of alcohol and water contains $54 \%$ water by mass. What is the mole fraction of ethanol?

What is the mass of glucose in $500 \ g$ of an aqueous solution of glucose with a molality of $0.5 \ m$?

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)

The strength of a solution $(S)$ in $g/L$ is related to its normality $(N)$ and equivalent weight $(E)$ of the solute by the formula:

$A$ $40 \%$ by mass sucrose solution is heated till it becomes $50 \%$ by mass. Calculate the mass of water lost from $100 \ g$ of the solution. (in $g$)