17-4

**Mega Lab Stations** //<---Previous Assignment - Next Assignment--->media type="custom" key="6581995"// 1. Groups of 4 2. Copy only the answer sheet below on to your wiki titled 17-4 to get credit for this lab. Delete the instructions after use if you copy them also. 3. Carry 1 computer per group around and copy the work to other’s wikis when you are done. 4. Plug in your laptops at the end of each class, but do not let cords dangle.
 * __Time Length__ **
 * **3 days**
 * __Instructions__ **


 * __Lab__ **

**Part I – Mixture v Compound** 1. Get 10 ml of vinegar & 10 ml of baking soda each in a 50 mL beaker. 2. Find the mass of both (including the beakers) and record it on your wiki 3. Mix them and record at least 2 observations on your wiki. (one must be if it is a chemical or physical reaction) 4. Find the mass of the now mixed chemicals (including the beakers) 5. If it lost mass, where did it go? (Or was it destroyed in the reaction?) 6. Is the resulting product a mixture or a compound? (mixtures are physical combinations of compounds and compounds are chemical combinations of compounds to make new compounds). 7. If it is a mixture, is it a solution? (solutions are uniformly mixed, aka homogeneous) 8. If it is a mixture, which of the two compounds is the solvent (thing that does the dissolving)? 9. Wash and dry your beakers

**Part II - Mixture v Compound** 1. Get 10 mL of sodium chloride and 20 mL of water e ach in a 50 mL beaker.

2. Find the mass of both (including the beakers) and record it on your wiki. 3. Mix them and record at least 2 observations on your wiki. (one must be if it is a chemical or physical reaction) 4. Find the mass of the now mixed chemicals (including the beakers) 5. If it lost mass, where did it go? (Or was it destroyed in the reaction?) 6. Is the resulting product a mixture or a compound? (mixtures are physical combinations of compounds and compounds are chemical combinations of compounds to make new compounds). 7. If it is a mixture, is it a solution? (solutions are uniformly mixed, aka homogeneous) 8. If it is a mixture, which of the two compounds is the solvent (thing that does the dissolving)? 9. Wash and dry your beakers **Part III – Solubility** 1. Fill 3 250 mL beakers with 150 mL of water each 2. At the same time drop a sugar cube in 1, and pour the packets of sugar in the other two. 3 . In one of the granulated samples stir it with a stirring rod. 4. Record the order in which each sample dissolves. (if you get tired of watching you may record what will happen once it becomes obvious.) 5. If you heated a mixture of sugar and water would it dissolve faster than a cold mixture? 6. Think about the gas in a Dr. Pepper. If you decrease the pressure (open it) what happens to the gas? Now think about the gasses floating around in your blood (Nitrogen, carbon dioxide, and oxygen). 7. If you dove down deep under the ocean where the pressure is very high what would happen to those gasses? (use the word dissolve in your answer) (p.s. when you come back up the pressure decreases and the gasses form bubbles as they undissolve (like opening a shaken dr pepper) if you do it fast, you die… =(. )

**Part IV – Specific Heat** 1. Keep electronics away from the fire/balloons. Put 50 mL of water into a balloon and blow it up (about 9 inches in diameter). Blow up another balloon to an equal size without water. 2. (light the Bunsen burner). Place the waterless balloon 6 inches above a flame with the knot pointing up. Count how long it takes 3. Record what happens. =) 4. Place the water balloon over the flame in the same way for while. (theoretically it shouldnt pop as quickly)  5. Record what happens (or didn’t happen)  6. Since water has a higher specific heat than air (it can absorb more heat before getting hotter), explain what happened?  7. If you lived in a place near water do you think the temperature would be more stable or would the sun heat the place more than a dry place?

**Part V – Electrolytes & pH** 1. Electrolytes are solutions that have ionized. (like salt (NaCl) breaking apart into Na+ and Cl- ions). They are called electrolytes because they conduct electricity. 2. Put the conductivity tester in the solutions listed below. Describe the brightness of the bulb for each one. 3. Salt water, tap water, pure salt, sugar water, 1 M HCl (strong acid), coffee (weak acid), Windex (weak base), and 1 M NaOH (strong base). 4) Tear 5 pieces of pH paper about 1 inch long. 5) Without dropping them, dip them in each of the acids, bases, and the pure water. Record their pH according to the color scale on the pH paper container (do it next to their conductivity on the answer sheet) 6) Throw away the used pH paper. 7) Is something with a pH of 6 a stronger acid than something with a pH of 1? (google pH line) 8) What number represents the strongest base? The weakest base?

**Part I** 1) Mass of vinegar & baking soda and 2 beakers
 * __Answer Sheet__ **

2) 2 Observations

3) Mixed mass

4) Answer

5) Answer

6) Answer

7) Answer  **Part II**   8) Mass of salt and water and beakers

9) 2 Observations

10) Mixed mass

11) Answer

12) Answer

13) Answer

14) Answer  **Part III**   15) Order that they dissolve

16) Answer

17) Answer

18) Answer

**Part IV** 19) What happened

20) What happened

21) Answer

22) Answer

**Part V** 23) Salt water

24) Tap water

25) Salt

26) Sugar water

27) 1 M HCl (strong acid)

28) Coffee (weak acid)

29) Windex (weak base)

30) NaOH (strong base)

31) Pure Water

32) Answer

33) Answer