Concentration: definition in chemistry
Concentration: The amount of solute present in a given amount of solution or solvent.
Concentration can be expressed in several ways: moles per liter (molarity), grams per liter, percent by mass or volume, or parts per million (ppm) for very small amounts. A concentrated solution contains a lot of solute and a dilute one contains little, and adding solvent lowers the concentration without changing the amount of solute. That fact gives the dilution equation c₁V₁ = c₂V₂, which is used to prepare solutions in the lab.
Examples
- Household vinegar — about 5% acetic acid
- Carbon dioxide in air — a little over 420 ppm
- Concentrated hydrochloric acid — about 12 mol/L
- Diluting 10 mL of 2 M acid to 100 mL gives 0.2 M