The mole fraction and molality of alcohol, C₂H₅OH, in 85°proof vodka is 0.186 and 12.70 mol/kg respectively.
<h3>Data provided:</h3>
- Molality = moles of solute/kilogram of solvent
- Mole fraction = number of moles of solute/ total number of moles
- Density = mass/volume
- number of moles = mass/molar mass
- molar mass alcohol, C₂H₅OH = 46 g/mol
- molar mass of water = 18 g/mol
- density of water = 1 g/mL
- density of alcohol = 0.79 g/mL
<h3>Calculating moles of solute</h3>
85° proof vodka = 1/2 * 85% v/v
85° proof vodka = 42.5 % alcohol
In 100 mL vodka:
Volume of alcohol = 42.5 mL
volume of water = 57.5 mL
mass of alcohol, C₂H₅OH = density * volume
mass of alcohol, C₂H₅OH = 0.79 * 42.5
mass of alcohol, C₂H₅OH = 33.575 g
moles of alcohol = 33.575 g / 46 g/mol
moles of alcohol = 0.730 moles
<h3>Calculating mole fraction</h3>
mass of water = 57.5 ml * 1 g/mL
mass of water = 57.5 g
moles of water = 57.5 g/ 18 g/mL
moles of water = 3.194 moles
Total moles = 3.194 + 0.730
Total moles = 3.924 moles
Mole fraction of alcohol = 0.730/3.924
Mole fraction of alcohol = 0.186
<h3>
Calculating molality of alcohol</h3>
mass of solvent = 57.5 = 0.0575 kg
Molality of alcohol = 0.730 / 0.0575
Molality of alcohol = 12.70 mol/kg
Therefore, the mole fraction and molality of alcohol, C₂H₅OH, in 85°proof vodka is 0.186 and 12.70 mol/kg respectively.
Learn more about mole fraction and molality at: brainly.com/question/10861444
