What are concentration?

Answer:
What IS concentration. Concentration is the number of moles in every thousand liters. Moles are the basic measurement units of atoms. And if you don't know what liters are, you should stop right now.
First answer by Res0zsfaindahouse. Last edit by Res0zsfaindahouse. Contributor trust: 1 [recommend contributor recommended]. Question popularity: 2 [recommend question].