Solution:
Solvent:
Solute:
homogeneous mixture of two or more substances.
the component of a solution that exists in greater quantity. the component of the solution that exists in smaller quantity.
Concentration: amount of a substance present in a given volume of solution.
Concentrated: has relatively large amount of substance present in a given volume of
Dilute: solution. has relatively small amount of substance present in a given volume of solution.
Molar concentration or Molarity: number of moles of a particular substance in one liter of solution.
Unit for Molarity: “mole/L” or “M”
1.0 M is read as “ 1.0 MOLAR”
Symbol for concentration:
The Formula for concentration:
[ ] e.g. [NaCl] = 1.2 M
Molar Concentration (c) = moles (n) c = molar concentration
Volume (V) n = number of moles
V = volume, in litres
Examples:
1.
What is the molar concentration of 5.12 g of NaCl that is made into a 250.0 mL of solution?
- convert grams into moles moles of NaCl = 5.12 g x
[NaCl] = n =
1 mol =
58.5 g
0.0875 mol =
V 0.2500 L
0.0875 mol
0.350 M
2.
What mass of NaOH is contained in 2.0 L of 0.200 M NaOH?
- solve for number of moles n = c x V n = 0.200 mol/L x 3.50 L = 0.700 mol mass = 0.700 mol x 40.0 g /1mol = 28.0 g

3.
What is the molarity of pure suphuric acid, H
2
SO
4
, having a density of 1.839 g/mL?
Density =
[H
2
SO
4
] = amount (mass)
Volume
1.839 g
0.001 L x molarity=
1 mol =
98.1 g amount (as mole)
Volume
18.7 M
4.
What is the molarity of CaCl
2
in solution made by dissolving and diluting 15.00 g of CaCl
2
6H
2
O to 500.0 mL?
When CaCl hydrate.
2
6H
2
O dissolves, the moles of CaCl
2
produced is equal to the moles of the
Number of moles = 15.00 g x 1 mole/ 219.1 g =
[CaCl
2
] = [CaCl
2
6H
2
O] = ________ = 1.369M
0.500 L
5.
How would you make a 0.500 L solution of 0.20 M Potassium permanganate?
6.
How many molecules are there in the solution above (question 5)?