1. Concentration of Solute

2. Concentration of Solute
The amount of solute in a solution is given by its concentration.
Molarity ( M ) =
moles solute
liters of solution

3. Another Concentration Unit: Add
MOLALITY, m
m of solution =
moles solute
kilograms solvent

4. Concentration of solutions (Molarity and Molality)
Molarity (M)
M =
moles of solute
liters of solution
Molality (m)
m =
moles of solute
mass of solvent (kg)
12.3

5. Molarity (M) = moles of solute Liters of solution M = mole A
L solution
EX: grams of calcium chloride are dissolved in enough water to make 750. mL of solution. What is the molarity of this solution?
*Remember*
1L = 1000mL
75.0 g CaCl2
1 mol
= CaCl2
110 g CaCl2
= M
0.750 L

6. Molality (m) = moles solute kg solvent m = mole A kg B *Remember*
1g = 1mL for H2O
1000g = 1 kg
Ex: What is the molality of a solution if 4.8g NaCl is dissolved in 500 ml of H20?
0.5 kg
4.8 g NaCL
1 mol
= mol NaCl
58.5 g NaCl
= m

7. Concentration Units % mass (Percent by Mass)
The concentration of a solution is the amount of solute present in a given quantity of solvent or solution.
x 100%
mass of solute
mass of solute + mass of solvent
% by mass = =
x 100%
mass of solute
mass of solution

8. Molarity & Dilution of Solution
M1V1 = M2V2
MConVCon = MdiluteVdilute