1. NSCI 310 Homework 6 Due 2/15/07 Describe your observations for your chemical reactions experiments. Discuss what happened during your chemical reactions using the terms introduced for heat in class. Convert your temperatures to Fahrenheit.

2. Rattlebacks: Disequilibrium Ch. 2 p. 34

3. Chapter 13: Power Power = Energy per time Why not Energy Plants?

4. GRACE Variations around  0.0006 m/s 2 out of 9.8 m/s 2 Red: highest Blue: lowest Earth’s Gravity

5. Pattern: The Harmony of the Spheres ISS(90 min): 6.8 x 10 6 m Geosynchronous(24 hr): 4.2 x10 7 m

6. Matter: Periodic Table Patterns

7. Pressure Demonstrations Plastic Cup Water Plastic Cover ?

8. Pressure Demonstrations Plastic Cup Water Plastic Cover ? Small Hole

9. Pressure Demonstrations Plastic Cup Water Plastic Cover ? Small Hole

10. Predict how far I can project the ping pong ball with the funnel gun with my best shot. A. across the room B. half way across the room C. barely out the funnel D. not at all

11. Blowing out a candle.

12. Both can be explained by the conservation of mass

13. The reasoning--though incomplete--is based on the Bernoulli effect, which correctly correlates the increased speed with which air moves over a surface and the lowered air pressure measured at that surface. In fact, most airplane wings do have considerably more curvature on the top than the bottom, lending credence to this explanation. But, even as a child, I found that it presented me with a puzzle: how can a plane fly inverted (upside down). When I pressed my 6th grade science teacher on this question, he just got mad, denied that planes could fly inverted and tried to continue his lecture. I was very frustrated and argued until he said, "Shut up, Raskin!"

14. Here's what happened: he sent me to the principal's office when I came in the next day with a balsa model plane with dead flat wings. It would fly with either side up depending on how an aluminum foil elevator adjustment was set. I used it to demonstrate that the explanation the class had been given must have been wrong, somehow. The principal, however, was informed that my offense was "flying paper airplanes in class" as though done with disruptive intent. After being warned that I was to improve my behavior, I went to my beloved math teacher who suggested that I go to the library to find out how airplanes fly--only to discover that all the books agreed with my science teacher!

15. Questions?

16. Chapter 14: Heat A. Heat is the transfer of energy through motions on the atomic level. B. Temperature in the intensity of the motion of the molecules. C. Heat and temperature aren’t the same.

17. Temperature vs. Heat A. Temperature like saltiness of sea B. Heat like amount of salt in the sea

18. Heat Transfer: Heating vs. Cooling A. Heating: transferring heat to the body B. Cooling: transferring heat out of the body C. Heat moves from a warmer body to a cooler body

19. Changes of state A. Heat Removed / Heat Added B. Freezing / Melting C. Condensing / Boiling D. Solidifying / Subliming E. Order / Disorder

20. Temperature scales A. Celsius T C = 5 (T F -32) / 9 B. Fahrenheit T F = 9T C / 5 + 32 C. Kelvin T K = T C + 273

21. Skating on Ice (p. 305) The change in the melting point of water due to the pressure on a typical skate blade is around – 0.05 C. At 20 below in northern Minnesota, this doesn’t explain how I can still skate. There is good evidence that there is an ultra-thin layer of quasi-liquid water on the surface if ice. Also friction provides some heat to melt the ice.

22. Come up and touch the blocks labeled A and B. Which block is at a higher temperature? A. Block A B. Block B. C. Both at the same temperature.

23. Block ABlock B Ice Cube

24. Chemical Reactions and Heat A. A chemical reaction the gives off heat to its surroundings is exothermic. B. A chemical reaction the takes heat from its surroundings is endothermic.

25. Chemical Reactions A. Stir your solution and wait for it to come to equilibrium before recording the “before” temperature. Why? B. Take your “after” temperature reading as soon after adding and stirring the ingredients as is reasonable. Don’t hold the base of your cup while stirring! Why? C. Stir your solution while you are waiting 3 minutes to be sure everything has a chance to react. Record your “ending” temperature after 3 minutes.