The molecular weight of urea is $60$. $A$ solution of urea containing $6 \ g$ of urea in one litre is ....... $molar$.

$A$ solution is obtained by mixing $300 \, g$ of $25 \%$ solution and $400 \, g$ of $40 \%$ solution by mass. Calculate the mass percentage of the resulting solution. (in $\%$)

The hardness of a water sample is due to $50 \, ppm$ of $MgSO_4$. Calculate the amount of $MgSO_4$ in $mg$ present per $kg$ of water.

The volumes of $4\,N\, HCl$ and $10\,N\, HCl$ required to make $1\, L$ of $6\,N\, HCl$ are

Calculate the molarity of a solution prepared by dissolving $7.1 \ g$ of sodium sulfate $(Na_2SO_4)$ in water to make $100 \ mL$ of solution. (in $M$)

The correct relationship between molality $(m)$ and molarity $(M)$ of a solution is ($d = $ density in $g/mL$ and $M_{solute} = $ molar mass of solute in $g/mol$)