Question 6
Why does shaking an aqueous iodine solution with carbon tetrachloride move the iodine into the carbon tetrachloride layer?
The right answer is the one marked above.
Iodine has a higher solubility in carbon tetrachloride, and the two solvents do not mix. Both conditions are needed: the higher solubility gives the iodine a reason to move, and the two solvents staying in separate layers is what lets you pour them apart afterwards.
The remarkable part is that a small volume of carbon tetrachloride is enough to extract the iodine from a large volume of the aqueous solution.