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Concept Explaination:

Imagine mixing a drop of oil into water. At first it floats on the surface; when you try to mix it into the water, it forms small individual droplets that are distributed throughout the water. These droplets then slowly get pushed out of the water until they're floating on the surface again, separate from the water.

This is an example of phase separation, where two liquids do not mix together because they are not soluble. Solubility is the ability for one compound to dissolve in another to form a uniform solution.

Polar solutes are soluble in polar solvents due to their dipole-dipole interaction. Non-polar molecules, due to their inability to form intermolecular bonds with polar molecules, will not be soluble in a polar solvent and will form a non-polar layer instead. This is often referred to as "like dissolves like".

When Olivia arrives at her new school (like a drop of oil being added to water), she wants to join the popular kids. These popular (polar) kids are brightly colored in a gradient to represent how modeling programs often represent the electronics of polar models. The other non-popular kids sit separately from the popular ones, and note that she's not like a popular kid at all, and she won't be fit in with them. Sure enough, when Olivia tries to mix into the popular kids, she briefly interacts with them as a small individual before the popular kids band together and push her out of their group where she then joins the non-popular kids who sit separately. In this case, Olivia represents a non-polar molecule which readily dissolves in a non-polar solvent, but does not dissolve in a polar solvent.

Remember that compounds are soluble with each other when they can form interactions! After all, it's much easier to hang out with people who are similar to you than people who aren't!

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