Final answer:
Beta-carotene, composed of two hydrocarbon rings without oxygen-containing groups, is more soluble in non-polar solvents, whereas xanthophylls have oxygenated functional groups that provide increased polarity and solubility in polar solvents. In a solvent with 9 parts per ether and 1 part acetate, beta-carotene is expected to be more soluble compared to xanthophylls.
Step-by-step explanation:
The structural differences between beta-carotene and xanthophyll are primarily due to the presence of oxygen-containing functional groups in xanthophylls, which are absent in beta-carotene. Beta-carotene is composed of two ß-ionone rings connected by an eighteen-member hydrocarbon chain that has methyl groups as substituents. This structure, with a long system of conjugated double bonds, makes it highly hydrophobic and soluble in non-polar solvents.
Xanthophylls, on the other hand, are oxygenated derivatives of carotenes. They include hydroxy or epoxy groups, which introduce some polarity to the molecule. Therefore, compared to beta-carotene, xanthophylls are expected to have increased solubility in polar solvents due to their ability to form hydrogen bonds, but reduced solubility in non-polar solvents. Considering a solvent that is 9 parts per ether (a non-polar solvent) and 1 part acetate (a polar solvent), beta-carotene is expected to be more soluble due to its non-polar nature, while xanthophylls will have only slightly increased solubility due to the small amount of the polar component (acetate) in the solvent mix.