If the mole fraction of the solute in liquid naphthalene $(C_{10}H_{8})$ is $0.2$,then the molality of the solution will be ............ $m$.

How many moles and grams of sodium chloride are present in $200 \ cm^3$ of $0.2 \ M \ NaCl$ solution?

What is meant by mass percentage $( \% w/w )$?

$A$ solution of sodium sulphate contains $92 \ g$ of $Na^{+}$ ions per kilogram of water. The molality of $Na^{+}$ ions in that solution in $mol \ kg^{-1}$ is:

$200 \ mL$ of a solution contains $5.85 \ g$ dissolved sodium chloride. The concentration of the solution will be .......... $molar$ $(Na = 23; Cl = 35.5)$.

The density of a stock solution of $29.2\% \, (w/w) \, HCl$ is $1.25 \, g \, mL^{-1}$. If the molar mass of $HCl$ is $36.5 \, g \, mol^{-1}$,what volume (in $mL$) of the stock solution is required to prepare $200 \, mL$ of $0.4 \, M \, HCl$ solution?