Answer:
Mass fraction = 0.08004
Mole fraction = 0.0377
Explanation:
Given, Mass of NaOH = 8.70 g
Mass of solution = 8.70 + 100 g = 108.70 g
[tex]Mass\ fraction\ of\ NaOH=\frac {8.70}{108.70}[/tex] = 0.08004
Molar mass of NaOH = 39.997 g/mol
The formula for the calculation of moles is shown below:
[tex]moles = \frac{Mass\ taken}{Molar\ mass}[/tex]
Thus,
[tex]Moles= \frac{8.70\ g}{39.997\ g/mol}[/tex]
[tex]Moles\ of\ NaOH= 0.2175\ mol[/tex]
Given, Mass of water = 100 g
Molar mass of water = 18.0153 g/mol
The formula for the calculation of moles is shown below:
[tex]moles = \frac{Mass\ taken}{Molar\ mass}[/tex]
Thus,
[tex]Moles= \frac{100\ g}{18.0153\ g/mol}[/tex]
[tex]Moles\ of\ water= 5.5508\ mol[/tex]
So, according to definition of mole fraction:
[tex]Mole\ fraction\ of\ NaOH=\frac {n_{NaOH}}{n_{NaOH}+n_{water}}[/tex]
[tex]Mole\ fraction\ of\ NaOH=\frac {0.2175}{0.2175+5.5508}=0.0377[/tex]
