Molality $(m)$ of $3 \text{ M}$ aqueous solution of $NaCl$ is:
(Given: Density of solution = $1.25 \text{ g mL}^{-1}$, Molar mass in $\text{g mol}^{-1}$: $Na = 23$, $Cl = 35.5$) (in $\text{m}$)

$50 \ mL$ of an aqueous solution of glucose contains $6.02 \times 10^{22}$ molecules. The concentration of the solution is? ........... $M$

Density of $12.25\%$ (by weight) $H_2SO_4$ solution is $1.056 \ g/mL$. The molarity of the solution is .......... $M$.

Molality of $30 \% \ w/w$ aqueous solution of $NaOH$ is . . . . . . . (in $m$)

$A$ $500 \ g$ toothpaste sample has $0.2 \ g$ fluoride concentration. What is the concentration of $F^-$ in terms of $ppm$ level?

The molarity of the solution prepared by dissolving $6.3 \ g$ of oxalic acid $(H_{2}C_{2}O_{4} \cdot 2H_{2}O)$ in $250 \ mL$ of water in $mol \ L^{-1}$ is $x \times 10^{-2}$. The value of $x$ is ..... . (Nearest integer)
[Atomic mass : $H: 1.0, C: 12.0, O: 16.0]$