91影视

Number of moles is defined as the mass of solute per molar mass of solute.

$\mathbf{\text{numberofmoles}}\mathbf{=}\frac{\mathbf{\text{尘补蝉蝉鈥塷蹿鈥塻辞濒耻迟别}}}{\mathbf{\text{尘辞濒补谤尘补蝉蝉鈥嬧赌夆赌媜蹿鈥塻辞濒耻迟别}}}$

Moles of fraction is defined as the moles of solute per total moles.

$\mathbf{\text{尘辞濒别蝉鈥塮谤补肠迟颈辞苍}}\mathbf{=}\frac{\mathbf{\text{尘辞濒别蝉鈥塷蹿鈥塻辞濒耻迟别}}}{\mathbf{\text{迟辞迟补濒鈥尘辞濒别蝉}}}$

^{Consider the equal mass of $尾$-pinene and $伪$-terpineol is $\text{10g}$.}

^{Molecular mass of $尾$-pinene is $\text{136.23}\raisebox{1ex}{$\text{g}$}\!\left/ \!\raisebox{-1ex}{$\text{mol}$}\right.$and molecular mass of $伪$-terpineol is $\text{154.25}\raisebox{1ex}{$\text{g}$}\!\left/ \!\raisebox{-1ex}{$\text{mol}$}\right.$.}

Determine the number of moles of $尾$-pinene as below.

$\begin{array}{rcl}\text{尘辞濒别蝉鈥塷蹿鈥�}尾鈭�pinene& =& \frac{\text{尘补蝉蝉鈥塷蹿}尾鈭�pinene\text{鈥�}}{\text{尘辞濒补谤鈥夆赌媘补蝉蝉鈥夆赌媜蹿鈥�}尾鈭�pinene}\\ & =& \frac{\text{10g}}{\text{136.23}{\displaystyle \raisebox{1ex}{$\text{g}$}\!\left/ \!\raisebox{-1ex}{$\text{mol}$}\right.}}\\ & =& 0.073\text{mol}\end{array}$

Define the number of moles of $伪$-terpineol as follow.

$\begin{array}{rcl}\text{尘辞濒别蝉鈥塷蹿鈥�}伪鈭�terpineol& =& \frac{\text{尘补蝉蝉鈥塷蹿鈥�}伪鈭�terpineol\text{鈥�}}{\text{尘辞濒补谤鈥夆赌媘补蝉蝉鈥夆赌媜蹿鈥�}伪鈭�terpineol\text{鈥�}}\\ & =& \frac{\text{10g}}{\text{154.25鈥媑}/\text{mol}}\\ & =& \text{0.064mol}\end{array}$

Calculate the total moles as follow.

$\begin{array}{rcl}\text{罢辞迟补濒鈥夆赌媘辞濒别蝉}& =& 0.73\text{moles}+0.64\text{moles}\\ & =& 1.37\text{moles}\end{array}$

Determine the moles of fraction for $尾$-pinene as below.

$\begin{array}{rcl}\text{尘辞濒别蝉鈥塮谤补肠迟颈辞苍鈥塷f鈥�}尾鈭�pinene& =& \frac{moles\text{鈥�}of\text{鈥�}尾鈭�pinene}{total\text{鈥�}moles}\\ & =& \frac{\text{0.73mol}}{\text{1.37mol}}\\ & =& 0.53\end{array}$

Define the moles of fraction for $伪$-terpineol as follow.

$\begin{array}{rcl}\text{尘辞濒别蝉鈥塮谤补肠迟颈辞苍鈥塷f鈥�}伪鈭�terpineol& =& \frac{\text{尘辞濒别蝉鈥塷蹿鈥�}伪鈭�terpineol}{\text{迟辞迟补濒鈥尘辞濒别蝉}}\\ & =& \frac{\text{0.64mol}}{\text{1.37mol}}\\ & =& 0.46\end{array}$

Partial vapor pressure of solution containing $尾$-pinene can be calculated by multiplying mole fraction of $尾$-pinene and the given partial vapor pressure of pure $尾$-pinene $\left(100.3\text{torr}\right)$.

$\begin{array}{rcl}{P}_A& =& {蠂}_A脳{P_A}^{鈭�}\\ & =& 0.53脳100.3\text{torr}\\ & =& 53.159\text{torr}\end{array}$

Partial pressure of solution containing $伪$-terpineol can be calculated by multiplying the mole fraction of $伪$-terpineol and given partial vapor pressure of $伪$-terpineol $\left(9.8\text{torr}\right)$.

$\begin{array}{rcl}{P}_B& =& {蠂}_B脳{P_B}^{鈭�}\\ & =& 0.46脳9.8\text{torr}\\ & =& 4.508\text{torr}\end{array}$

Composition of vapor of a solution in terms of mole fraction can be calculated by dividing partial vapor pressure one component by sum of partial vapor pressure of both components.

Sum of partial vapor pressure of both solution

Composition of vapor for -pinene is,

$\begin{array}{rcl}P& =& P_A+P_B\\ & =& 53.569\text{torr}+4.508\text{torr}\\ & =& 58.077\text{torr}\end{array}$

Composition of vapor for $尾$-pinene is,

role="math" localid="1663336947199" $\begin{array}{rcl}\frac{P_B}{P}& =& \frac{53.569\text{torr}}{58.077\text{torr}}\\ & =& 0.922\end{array}$

Composition of vapor for $伪$-terpineol is,

$\begin{array}{rcl}\frac{P_A}{P}& =& \frac{4.508\text{torr}}{58.077\text{torr}}\\ & =& 0.077\end{array}$

Hence, the composition of vapor (in terms of mole fractions) is$0.92$ and $0.077$.