The density of $NH_4OH$ solution is found to be $0.6 \, g/mL$. It contains $35 \%$ by mass of $NH_4OH$. The normality of the solution is ......... $N$.

The mole fraction of urea in an aqueous urea solution containing $900 \text{ g}$ of water is $0.05$. If the density of the solution is $1.2 \text{ g cm}^{-3}$,the molarity of the urea solution is . . . . . (Given data: Molar masses of urea and water are $60 \text{ g mol}^{-1}$ and $18 \text{ g mol}^{-1}$,respectively)

The molarity of $20\% \,(W/W)$ solution of sulphuric acid is $2.55 \, M$. The density of the solution is $........... \, g \, cm^{-3}$.

Which of the following modes of expressing concentration is independent of temperature?

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

Assertion: One molal aqueous solution of glucose contains $180 \, g$ of glucose in $1 \, kg$ water.
Reason: Solution containing one mole of solute in $1000 \, g$ of solvent is called one molal solution.