What is the mole fraction of ethanol when 5.00 mL of ethanol are combined with 10.00 mL of water?
To find the mole fraction of ethanol in the solution, you'll need to know the amount of ethanol and water in terms of moles. From there, you can calculate the mole fraction.
First, you need to determine the number of moles of ethanol and water. To do this, you'll use the given volumes and the known density of ethanol. The density of ethanol is around 0.789 g/mL.
1. Calculate the mass of ethanol:
mass = density × volume
mass = 0.789 g/mL × 5.00 mL
2. Convert the mass of ethanol to moles:
moles = mass / molar mass
The molar mass of ethanol (C₂H₆O) is approximately 46.07 g/mol.
Next, calculate the same quantities for water:
1. Calculate the mass of water:
mass = density × volume
density of water = 1.00 g/mL
mass = 1.00 g/mL × 10.00 mL
2. Convert the mass of water to moles:
moles = mass / molar mass
The molar mass of water (H₂O) is approximately 18.02 g/mol.
Now you have the number of moles of ethanol and water in the solution. To find the mole fraction of ethanol:
1. Calculate the total moles of the solution:
total moles = moles of ethanol + moles of water
2. Calculate the mole fraction of ethanol:
mole fraction of ethanol = moles of ethanol / total moles
By using the above calculations, you can determine the mole fraction of ethanol in the solution.