What will be the molality of a solution having $18 \ g$ of glucose (mol. wt. $= 180$) dissolved in $500 \ g$ of water?

Sea water,which can be considered as a $6 \ M$ solution of $NaCl$,has a density of $2 \ g \ mL^{-1}$. The concentration of dissolved oxygen $(O_2)$ in sea water is $5.8 \ ppm$. Then the concentration of dissolved oxygen $(O_2)$ in sea water is $x \times 10^{-4} \ m$. $x = ............$ $(Nearest \ integer)$
Given: Molar mass of $NaCl$ is $58.5 \ g \ mol^{-1}$. Molar mass of $O_2$ is $32 \ g \ mol^{-1}$.

Explain molarity and molality in short.

Calculate the amount of benzoic acid $(C_{6}H_{5}COOH)$ required for preparing $250 \ mL$ of $0.15 \ M$ solution in methanol.

Calculate $(a)$ molality,$(b)$ molarity,and $(c)$ mole fraction of $KI$ if the density of $20 \%$ (mass/mass) aqueous $KI$ solution is $1.202 \, g \, mL^{-1}$.

What volume (in $mL$) of $3.0 \ M \ H_2SO_4$ is required to prepare $1.0 \ L$ of a $1.0 \ M$ solution?