Concentration

Determining the Concentration Concentration = Quantity of solute Quantity of Solution (Solute+Solvent )

Two Classifications of Concentration Concentrated: large amount of solute per unit volume of solution Dilute: small amount of solute per unit volume of solution

Concentration Concentrations are most often seen as a percent Percent = Quantity of solute X 100 Concentration Quantity of Solution

Percent Concentration Two ways to calculate percent Weight / Volume OR Volume / Volume (W/V) (V/V) 12%(W/V) = 12g 12%(V/V) = 12 mL 100mL 100mL

Molar Concentration Molar = Amount of Solute = moles Concentration Amount of Solution Liters Molar = mol/L = M

Using Percent to calculate the amount of a solute in a sample Calculate the amount of calcium chloride in 300mL of a 15%(W/V) solution CaCl 2 1)Convert percent to a fraction: 15g/100mL

Using Percent to calculate the amount of a solute in a sample Calculate the amount of calcium chloride in 300mL of a 15%(W/V) solution CaCl 2 1)Convert percent to a fraction: 15g/100mL 2)Starting with a question mark cancel out the units to find the unit you are looking for

Using Percent to calculate the amount of a solute in a sample Calculate the amount of calcium chloride in 300mL of a 15%(W/V) solution CaCl 2 1)Convert percent to a fraction: 15g/100mL 2)Starting with a question mark cancel out the units ?g CaCl2 = 300mL

Using Percent to calculate the amount of a solute in a sample Calculate the amount of calcium chloride in 300mL of a 15%(W/V) solution CaCl 2 1)Convert percent to a fraction: 15g/100mL 2)Starting with a question mark cancel out the units ?g CaCl2 = 300mL X 15g = 45g 100mL

Using Percent to calculate the amount of a solute in a sample How would you determine the volume you would need in order to get 23g of FeO from a 53% (W/V) solution? 1) 53g FeO /100mL

Using Percent to calculate the amount of a solute in a sample How would you determine the volume you would need in order to get 23g of FeO from a 53% (W/V) solution? 1)53g FeO /100mL 2)?mL = 23g FeO

Using Percent to calculate the amount of a solute in a sample How would you determine the volume you would need in order to get 23g of FeO from a 53% (W/V) solution? 1)53g FeO /100mL 2)?mL = 23g FeO X 100mL = 43mL 53g FeO

Using molar concentration to find the number of moles How many moles of NaCl are found in a 0.2L sample of 3M (M=mol/L) NaCl? 1)?mols = 0.2L

Using molar concentration to find the number of moles How many moles of NaCl are found in a 0.2L sample of 3M (M=mol/L) NaCl? 1)?mols = 0.2L X 3mol = 0.6 mol 1L