1. S OLUTION C ONCENTRATION : M OLARITY 14.2 : Pgs 480 - 488

2. M AIN I DEA … Using the unit of molarity to express solution concentration and perform dilutions

3. M OLARITY Molarity (M): number of moles of solute per liter of solution (shows us how concentrated a solution is)

4. M OLARITY Things to note in molarity: The amount of solution is the TOTAL amount of solution, NOT the total amount of solvent! Ex: A 0.50 M solution contains 0.50 mole of solute in a 1.0 L solution

5. C ALCULATING M OLARITY A solution has a volume of 2.0 L and contains 36.0 g of glucose. If glucose has a molar mass of 180. g/mol, what is the molarity of the solution?

6. C ALCULATING M OLARITY A solution has a volume of 250 mL and contains 0.70 mol of NaCl. What is the molarity of the solution? M = mol/L = 0.70mol /.250L M = 2.8M

7. O THER M OLARITY C ALCULATIONS How many grams of ammonium nitrate are in 335 mL of 0.425 M NH 4 NO 3 ?

8. M AKING D ILUTIONS If I have a stock solution, is there an easy way for me to make dilutions? – yes! M 1 V 1 = M 2 V 2 Example: How many milliliters of a stock solution of 4.00 M KI would you need to prepare 250.0mL of 0.760 M KI? How many milliliters of a stock solution of 4.00 M KI would you need to prepare 250.0mL of 0.760 M KI?

9. L AB A CTIVITY Complete the lab activity Objectives: Create a stock solution of sugar water Dilute the stock solution to the desired molarity Determine the density of this solution For an extra credit point to your test: Your final density must have less than a 35% error. But… before you go to the lab answer this question. After the lab you should work on your textbook homework.

10. B EFORE YOU GO … How many grams of solute are in 250 mL of 2.0 M calcium chloride?