Question

Calculate the mole fraction of ethanol if 9.2g of it is mixed with 1.8g water

Answer 1

Answer:

0.667

Explanation:

Calculate the moles of ethanol

moles=Given mass /Molar mass

9.2/46=0.2moles

similarly moles of water is 0.1

Mole fraction =Moles of solute/Moles of solution

0.2/0.2+0.1

=0.2/0.3

=0.667

Hope this answer will help you

Answer 2

Answer: The mole fraction of ethanol is 0.655

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

• For ethanol:

Given mass of ethanol = 9.2 g

Molar mass of ethanol = 46.07 g/mol

Putting values in above equation, we get:

$\text{Moles of ethanol}=\frac{9.2g}{46.07g/mol}=0.19mol$

• For water:

Given mass of water = 1.8 g

Molar mass of water = 18 g/mol

Putting values in above equation, we get:

$\text{Moles of water}=\frac{1.8g}{18g/mol}=0.1mol$

• Mole fraction of ethanol is calculated by using the formula:

$\chi_{ethanol}=\frac{n_{ethanol}}{n_{ethanol}+n_{water}}$

Putting values in above equation, we get:

$\chi_{ethanol}=\frac{0.19}{0.19+0.1}=0.655$

Hence, the mole fraction of ethanol is 0.655