The attractive intermolecular forces between the Allura Red molecule and either the water or ethyl acetate molecule can be quantified by subtracting the energies of the isolated molecules, ions, or both from the energy of the pair. These Excess energies can be compared to determine which pair has stronger intermolecular forces. Use the energies found from the calculations in the previous two questions (Energy of Single Isolated Molecules/Ions and Energy of Allura Red and Water or Ethyl Acetate Pairs) to determine the excess energy for each molecular combination.
Note: The more negative an energy, the more stable a molecule or group of molecules is.
Molecule combination: Allura Red plus ethyl acetate. Excess energy: kJ/mol
Molecule Combination: Allura Red plus 5 waters. Excess energy kJ/mol
Based on the excess energies, which solvent has a higher affinity for Allura Red dye?
a. ethyl acetate
b. water