1. Concentration of Solutions

2. Concentration
The concentration of a solution is a measure of the amount of solute in a given amount of solvent or solution.
Dilute: a relatively small amount of a solute in a solvent.
Concentrated: a relatively large amount of a solution in a solvent.

3. Molarity The number of moles of a solute in one liter of solution.
For example: a 1 M solution of Sodium hydroxide contains one mole of NaOH for every 1 Liter of solution.
The unit for molarity is M

4. Molarity We can express molarity using the following equation:
Molarity (M) = amount of solute (mol)
volume of solution (L)

5. Example
You have 3.50 L of a solution that contains 1.54 mol of Sodium Chloride. What is the molarity of the solution?
You have 6.2 L of a solution that contains 0.2 mol if Ca(OH)2. What is the molarity of the solution?

6. Rearranging the Molarity Equation

7. Steps: Determine which variables you know.
Convert variables into the correct units.
Determine which equation you are going to use OR plug in the information you know into the molarity equation.
Write your answer and include units.

8. Example
You have 0.8 L of 0.5 M solution of HCl. How many moles of HCl does this solution contain?

9. Example
What volume is needed for a 3.00 M NaCl solution that contains g of NaCl?