If $5.85 \ g$ of $NaCl$ is dissolved in $72 \ g$ of water,find the mole fraction of $NaCl$.

Dissolving $120 \ g$ of a compound (mol. wt $= 60$) in $1000 \ g$ of water gave a solution of density $1.12 \ g \ mL^{-1}$. The molarity of the solution is: (in $M$)

Calculate the molarity of ethanol in a solution where the mole fraction of ethanol is $0.040$. (Assume the density of water is $1 \ g/mL$.) (in $M$)

$A$ solution of sugar is obtained by mixing $200 \ g$ of its $25 \%$ solution and $500 \ g$ of its $40 \%$ solution (both by mass). The mass percentage of the resulting sugar solution is $..........$. (Nearest integer)

How are $0.50 \, mol$ $Na_{2}CO_{3}$ and $0.50 \, M$ $Na_{2}CO_{3}$ different?

If $100 \ g$ of a $0.2 \ m$ aqueous solution is diluted by adding $200 \ g$ of water,what will be the molality of the resulting solution?