|MadSci Network: Chemistry|
Oils are generally less dense than water. The unit weight per volume of oil, or density, is less than that of water. The oil then floats. There are some oils that are more dense than water and sink into the water. You may have read or seen the news of oil spills in the ocean that were partially submerged. The density of these spills were close to the density of water and make them difficult to clean up.
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