Question #838b2

1 Answer
Oct 14, 2016

There are two reasons. The difference in densities and the difference in molecular polarity.


Oil being less dense than water, when the two are mixed, oil floats above water.

Oil being non-polar and water being polar (with two hydrogen molecules and one oxygen molecules), they tend to stick to their own kind (oil-oil and water-water) preferentially and repel each other.