Answer:
The mole fraction of codeine is 5.4%
Step-by-step explanation:
Mole fraction = Mole of solute / Total moles (Mole solute + Mole solvent)
Solute (Codeine)
Molar mass 299.36 g/m
Mass / Molar mass = Mole → 46.85 g /299.36 g/m = 0.156 moles
Solvent (Ethanol)
Molar mass 46.07 g/m
125.5 g / 46.07 g/m = 2.724 moles
Mole fraction (Codeine) 0.156 / (0.156 + 2.724) → 0.054