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

The molar concentration of chloride ions in the resulting solution of $300 \ mL$ of $3.0 \ M$ $NaCl$ and $200 \ mL$ of $4.0 \ M$ $BaCl_{2}$ will be (in $M$)

The density of $3 \text{ M}$ solution of sodium chloride is $1.252 \text{ g mL}^{-1}$. The molality of the solution will be ............. $\text{m}$. (molar mass,$NaCl = 58.5 \text{ g mol}^{-1}$)

What mass of ethanol in $g$ must be added to $1.0 \, kg$ of water to have a mole fraction of ethanol equal to $0.2$?

What will be the molality of the solution containing $18.25 \ g$ of $HCl$ gas in $500 \ g$ of water (in $m$)?

The sum of the mole fraction of the components of a solution is