91Ó°ÊÓ

Solution can be formed from thedissolution of the solute in the solvent. The solute decides the nature of the solution.

Molality can be defined as the ratio of the mass of the solute to the mass of the solution present in kilogram measure.

$\mathbf{Molality}\mathbf{=}\frac{\mathbf{Number} \mathbf{of} \mathbf{Moles}}{\mathbf{Mass} \mathbf{of} \mathbf{the} \mathbf{Solution} \mathbf{(} \mathbf{in} \mathbf{kilogram} \mathbf{)}}$

Number of moles can be defined as the ratio of the mass of the atom/molecule and molar mass of the atom/molecule.

$\mathbf{Number} \mathbf{of} \mathbf{Moles}\mathbf{=}\frac{\mathbf{Mass}}{\mathbf{Molar} \mathbf{Mass}}$

Mole Fraction can be defined as the ratio of the number of moles of the solute to the number of moles of solvent and number of solute.

$\mathbf{Mole} \mathbf{Fraction}\mathbf{=}\frac{\mathbf{Number} \mathbf{of} \mathbf{Moles} \mathbf{of} \mathbf{One} \mathbf{Component}}{\mathbf{Number} \mathbf{of} \mathbf{Moles} \mathbf{of} \mathbf{the} \mathbf{Solvent}\mathbf{+}\mathbf{Number} \mathbf{of} \mathbf{Moles} \mathbf{of} \mathbf{Solute}}$

Parts by mass: It can be defined as the percentage of the ratio of the mass of solute to the total mass of the solution.

$\mathbf{Mass}\%\mathbf{=}\frac{\mathbf{Mass} \mathbf{of} \mathbf{Solute}}{\mathbf{Mass} \mathbf{of} \mathbf{the} \mathbf{Solution}}\mathbf{×}\mathbf{100}$

Density can be defined as the ratio of the mass of the matter to the volume of the matter.

$\mathbf{Density}\mathbf{=}\frac{\mathbf{Mass}}{\mathbf{Volume}}$

Volume of Water$\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{400}\mathbf{L}\mathbf{=}\mathbf{400}\mathbf{mL}$

Density of the Water $\mathbf{=}\mathbf{1}\mathbf{.}\mathbf{0}\mathbf{g}\mathbf{/}\mathbf{mL}$

$$\begin{gathered} \mathbf{Density}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{Water}\mathbf{=}\frac{\mathbf{Mass}}{\mathbf{Volume}} \\ \mathbf{1}\mathbf{.}\mathbf{0}\mathbf{g}\mathbf{/}\mathbf{mL}\mathbf{=}\frac{\mathbf{Mass}}{\mathbf{400}\mathbf{mL}} \\ \mathbf{Mass}\mathbf{=}\mathbf{1}\mathbf{.}\mathbf{0}\mathbf{g}\mathbf{/}\mathbf{mL}\mathbf{×}\mathbf{400}\mathbf{mL} \\ \mathbf{Mass}\mathbf{=}\mathbf{400}\mathbf{g} \end{gathered}$$

Mass of water $\mathbf{=}\mathbf{400}\mathbf{g}$

localid="1659357918062" $$\begin{gathered} \mathbf{Number}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{Moles}\mathbf{=}\frac{\mathbf{Mass}}{\mathbf{Molar}\mathbf{ }\mathbf{Mass}} \\ \mathbf{NumberofMoles}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{Water}\mathbf{=}\frac{\mathbf{400}\mathbf{g}}{\mathbf{18}\mathbf{g}\mathbf{/}\mathbf{mol}} \\ \mathbf{NumberofMoles}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{Water}\mathbf{=}\mathbf{22}\mathbf{ }\mathbf{mol} \end{gathered}$$

Mass of KI $\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{30}\mathbf{g}$

Molar Mass of KI $\mathbf{=}\mathbf{166}\mathbf{g}\mathbf{/}\mathbf{mole}$

$$\begin{gathered} \mathbf{Number} \mathbf{of} \mathbf{Moles}\mathbf{=}\frac{\mathbf{Mass}}{\mathbf{Molar} \mathbf{Mass}} \\ \mathbf{NumberofMoles} \mathbf{of} \mathbf{KI}\mathbf{=}\frac{\mathbf{0}\mathbf{.}\mathbf{30}\mathbf{g}}{\mathbf{166}\mathbf{g}\mathbf{/}\mathbf{mol}} \\ \mathbf{NumberofMoles} \mathbf{of} \mathbf{KI}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{002}\mathbf{mol} \end{gathered}$$

Number of moles of water $\mathbf{=}\mathbf{22}\mathbf{mole}$

Number of KI ${\mathbf{n}}_{\mathbf{KI}}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{002}\mathbf{mol}$

$$\begin{gathered} \mathbf{Mole}\mathbf{ }\mathbf{Fraction}\mathbf{=}\frac{\mathbf{Number}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{Moles}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{One}\mathbf{ }\mathbf{Component}}{\mathbf{Number}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{Moles}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{the}\mathbf{ }\mathbf{Solvent}\mathbf{+}\mathbf{Number}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{Moles}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{Solute}} \\ \mathbf{Mole}\mathbf{ }\mathbf{Fraction}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{Kl}\mathbf{=}\frac{\mathbf{0}\mathbf{.}\mathbf{002}}{\mathbf{22}\mathbf{+}\mathbf{0}\mathbf{.}\mathbf{002}} \\ \mathbf{Mole}\mathbf{ }\mathbf{Fraction}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{Kl}\mathbf{=}\frac{\mathbf{0}\mathbf{.}\mathbf{002}}{\mathbf{22}\mathbf{.}\mathbf{002}} \\ \mathbf{Mole}\mathbf{ }\mathbf{Fraction}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{Kl}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{000091} \end{gathered}$$

Mass of solute, KI $\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{30}\mathbf{g}$

Mass of solvent, water $\mathbf{=}\mathbf{400}\mathbf{g}$

$$\begin{gathered} \mathbf{Mass}\%\mathbf{=}\frac{\mathbf{Mass} \mathbf{of} \mathbf{Solute}}{\mathbf{Mass} \mathbf{of} \mathbf{the} \mathbf{Solution}}\mathbf{×}\mathbf{100} \\ \mathbf{=}\frac{\mathbf{0}\mathbf{.}\mathbf{30}\mathbf{g}}{\mathbf{400}\mathbf{g}\mathbf{+}\mathbf{0}\mathbf{.}\mathbf{30}\mathbf{g}}\mathbf{×}\mathbf{100} \\ \mathbf{=}\frac{\mathbf{0}\mathbf{.}\mathbf{30}\mathbf{g}}{\mathbf{400}\mathbf{.}\mathbf{30}\mathbf{g}}\mathbf{×}\mathbf{100} \\ \mathbf{=}\mathbf{0}\mathbf{.}\mathbf{075}\mathbf{\%} \end{gathered}$$