Here's why:

* Polarity: Water is a polar solvent, meaning it has a positive and negative end due to the uneven sharing of electrons in the O-H bonds. Iodine, on the other hand, is a nonpolar molecule.

* "Like Dissolves Like": The general rule of solubility is "like dissolves like". Polar solvents dissolve polar solutes, and nonpolar solvents dissolve nonpolar solutes.

* Carbon Disulfide: Carbon disulfide (CS₂) is a nonpolar solvent. Since iodine is also nonpolar, it readily dissolves in carbon disulfide.

Result: You'll see a much more concentrated iodine solution in carbon disulfide compared to water. The solution in carbon disulfide will have a distinctive violet color, whereas the solution in water will be a very pale yellow.