If $0.0100 \ g$ of urea $[(NH_2)_2CO]$ is added to $0.3000 \ m^3$ of water,what is the molality of the urea solution?

If $15 \ g$ of $NaOH$ is dissolved in water to make $250 \ mL$ of solution,find the molarity of this solution in $M$.

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 ............ $m$.

Explain $\% \, w/V$ and $\% \, w/w$ in brief.

$A$ solution of two components containing $n_{1}$ moles of the $1^{st}$ component and $n_{2}$ moles of the $2^{nd}$ component is prepared. $M_{1}$ and $M_{2}$ are the molecular weights of component $1$ and $2$ respectively. If $d$ is the density of the solution in $g \ mL^{-1}$, $C_{2}$ is the molarity and $x_{2}$ is the mole fraction of the $2^{nd}$ component, then $C_{2}$ can be expressed as

$A$ 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)