Question

A solution is made by mixing 135 g of methanol (CH3OH) and 124 g of water. What is the mole fraction of methanol in this solution?

Answer 1

The mole fraction of methanol in the solution is calculated by dividing the number of moles of methanol by the total number of moles, resulting in approximately 0.3798.

Step-by-step explanation:

To calculate the mole fraction of methanol in a solution, you first need to determine the number of moles of both methanol and water in the mixture. The molar mass of methanol (CH3OH) is 32.04 g/mol, and the molar mass of water (H2O) is 18.015 g/mol.

1. Calculate the moles of methanol: number of moles = 135 g / 32.04 g/mol = 4.211 moles of CH3OH.
2. Calculate the moles of water: number of moles = 124 g / 18.015 g/mol = 6.882 moles of H2O.
3. Calculate the total number of moles: total moles = 4.211 moles of CH3OH + 6.882 moles of H2O = 11.093 moles.
4. Calculate the mole fraction of methanol: mole fraction of CH3OH = moles of CH3OH / total moles = 4.211 / 11.093 ≈ 0.3798.

The mole fraction of methanol in the solution is therefore approximately 0.3798.