Concentrated vs Dilute Solutions
Concentrations of Solutions Concentration = quantity of solute quantity of solution
A solution is dilute if there is a relatively small amount of solute per unit volume of solution. A solution is concentrated if there is a relatively large amount of solute per unit volume of solution.
Percentage concentration Concentrations of solutions are sometimes expressed as percentages especially on labels of consumer products.
Percentage concentration When the solute is a solid: (w/v) weight/volume c = mass of solute x 100% volume of solution The unit for the mass MUST be in grams. The unit for the volume MUST be in mL. i.e. The units must be g/mL *solution is solute + solvent
Percentage concentration When two liquids are mixed to make a solution: (v/v) volume/volume c = volume of solute x 100% volume of solution Units for both volumes must be the same. i.e. mL / mL or L / L
Concentrations of very small amounts ppm (parts per million) ppb (parts per billion) ppt (parts per trillion) ppm =grams (g) x 106 volume in mL
Used by Chemists: Molar Concentration molar = number of moles of solute concentration volume of solution in L C = n V (L) [ ] represents concentration Units: mol/L or M