1. Make up Labs
4.1 and 4.3

2. Experiment 4.1 Dissolving a solid in a liquid
Purpose, Hypothesis, and Materials should come from your own pre- lab based on section 4.1 of the green book and the following procedure
Procedure is on the next slide

3. Experiment 4.1 Dissolving a solid in a liquid Procedure
Collect materials
Add water to test tubes
A groups - 20 ml B groups – 5 ml
Add 0.3 g of orange solid
Place stopper on test tube and shake
If the solid completely dissolved, add 0.3 g more
Record observations and data
Keep track of total orange solid added
January 21, 2014

4. Experiment 4.1 Dissolving a solid in a liquid
Observations
How many grams did you add to the 20 ml test tube?
How many grams did you add to the 5 ml test tube?
How did the colors compare in each test tube throughout the experiment?
Conclusion
Restate hypothesis, was it supported, what evidence shows this, what are possible sources of error?

5. Lab 4.3: Comparing concentrations of solutions
Pre Lab – Due Tuesday January 28

6. Lab 4.3: Comparing concentrations of solutions
Purpose: To compare the concentration of saturated solutions
Hypothesis: None required for this experiment
Materials:
2 test tubes Evaporating dish
5 g of Sodium Chloride (NaCl) 6. Watch glass
5 g of Sodium Nitrate (NaNO3) 7. Burner stand
2 stoppers Burner

7. Lab 4.3: Comparing concentrations of solutions
Procedure:
Mass 5 grams of sodium chloride (A) or 5 grams of sodium nitrate (B)
Place substance in a test tube that contains 5 ml of water
Put the a stopper on the test tube and shake vigorously
Mass a clean dry evaporating dish and watch glass
Pour the liquid into the evaporating dish (be careful not to pour any of the undissolved solid in the evaporating dish).

8. Lab 4.3: Comparing concentrations of solutions
Procedure:
Mass the evaporating dish liquid and watch glass together (system before heating)
Place the watch glass on top of the evaporating dish.
Heat to dryness
Allow the evaporating dish to cool
Mass the evaporating dish with its contents and watch glass (system after heating)
Calculate the concentrations of the solutions.

9. Lab 4.3: Comparing concentrations of solutions
Data table for Sodium Chloride (Solution A)
Mass of evaporating dish and watch glass
67.95 g
Mass of system before heating
73.48
Mass of system after heating
69.46
Mass of dissolved solute
4.02
Volume of solvent 5 ml
Concentration of solution
.646
g/ml

10. Lab 4.3: Comparing concentrations of solutions
Data table for Sodium Nitrate (Solution B)
Mass of evaporating dish and watch glass
55.95 g
Mass of system before heating
66.05
Mass of system after heating
60.5
Mass of dissolved solute
5.55
Volume of solvent 5 ml
Concentration of solution
.765
g/ml

11. Lab 4.3: Comparing concentrations of solutions
Sodium Chloride
(A) (g/ml)
Sodium Nitrate (B)
(g/ml)
0.63
0.872
.65
.83
.96
.962
.586
.634
.646
.765
.714
.894

12. Lab 4.3: Comparing concentrations of solutions
Conclusion
Write a conclusion about which solution had the greater concentration and why.