Calculate the moles of the solute by the formula: moles of solute = mass of the solute / molecular mass of the solute compound.
Calculate the moles of the solvent by the formula: moles of solvent = mass of the solvent / molecular mass of the solvent compound.
Calculate the mole fraction of the solute by the formula: mole fraction of the solute = moles of the solute / (moles of the solute + moles of the solvent).
Calculate the mole fraction of the solvent by the formula: mole fraction of the solvent = moles of the solvent/(moles of the solute + moles of the solvent).