In chemistry,<unk>  is the measure of how much of a given substance there is mixed with another substance. This<unk> n apply to any sort of chemical mixture, but most frequently the<unk> ncept is limited to homogeneous solutions, where it refers to the amount of solute in a substance.
To<unk> ncentrate a solution, one must add more solute, or reduce the amount of solvent (for instance, by selective evaporation). By<unk> ntrast, to dilute a solution, one must add more solvent, or reduce the amount of solute.
Unless two substances are fully miscible there exists a<unk>  at which no further solute will dissolve in a solution. At this point, the solution is said to be saturated. If additional solute is added to a saturated solution, it will not dissolve (except in<unk> rtain circumstances, when supersaturation may occur). Instead,  phase separation will occur, leading to either<unk> existing phases or a suspension. The point of saturation depends on many variables such as ambient temperature and the precise chemical nature of the solvent and solute.
Analytical<unk>  includes all the forms of that substance in the solution.
Concentration
Saturation 
Action potential
Potential energy
Extraction ratio
Average
Fluency
Intensity 