I'm referring to densities of materials, not the number of particles per unit volume.
- Anybody can ask a question
- Anybody can answer
- The best answers are voted up and rise to the top
closed as not a real question by MετάEd, Andrew Leach♦, Matt E. Эллен♦, cornbread ninja 麵包忍者, tchrist Nov 21 '12 at 21:38
It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center.If this question can be reworded to fit the rules in the help center, please edit the question.
Density is a property of matter describing how closely packed together its molecules are (dictionary.com). It is essentially the same use as a population description where many people packed closely together is considered a dense population.
Because everything has a density, but different densities are relative, the closest thing to the opposite of Dense you can get is either an absence of matter all together or Not Dense, or Less Dense. I'm sorry I can't offer anything better, but in all my years learning and teaching chemistry, I don't believe I've ever seen or heard an actual opposite for the term.