Appendix D

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APPENDIX D Answer Key

Multiple Choice 1. b 2. c 3. a 4. b 5. a 6. a 7. a 8. c 9. a 10. a 11. a 12. b 13. b 14. b 15. b 16. b 17. c 18. b 19. b 20. a 21. d 22. b 23. b 24. a 25. a 26. c 27. a 28. d 29. b 30. a 31. c 32. c 33. d 34. a 35. d

36. b 37. c 38. a 39. a 40. b 41. b 42. a 43. c

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Test III. Classification A. 1. Non-electrolytes 2. Electrolytes 3. Non-electrolytes 4. Non-electrolytes 5. Non-electrolytes 6. Non-electrolytes

B. 1. Colloid 2. Colloid 3. Pure 4. Colloid 5. Solution 6. Colloids

Test IV. Explanation 1. Charles law states that the volume of a constant amount of gas held a constants pressure will vary in volume directly with absolute temperature. As far as this pertains to Scuba, hot air takes up more “room” in tank. So when tank is filled, the gas volume becomes denser pressure increases, and so does the temperature. So a newly filled tank may show a temperature and pressure. Later, if the tank cools down, the gas inside the tank also chills and condenses, causing a pressure drop. Thus, the tank will contain less than a tank that remained cooler on filling. 2. It is necessary for mountain climbers to carry a supply of oxygen and an oxygen mask with them on their ascent to a high peak because high altitude areas have lesser amount of air compared to sea level. The lesser the amount of air the harder to breath to humans. 3. The significance in determining the boiling point of a substance is that to know at what temperature things boil. It is very useful in determining the purity of a substance. If the boiling point of what you’ve got and see if it matches. If boiling point is the same, then it is a good indication that the compound is pure, otherwise it is not pure. 4. Electrolytes are minerals in your body that have an electric charge. They are in your blood, wine and body fluids. It is important to keep a balance of electrolytes in your body, because they affect the amount of water in your body, blood acidity (pH), muscle action, and to other important processes. 5. The blue color of the sky is due to Rayleigh scattering. As light moves through the atmosphere, most of the longer wavelengths pass straight through. Little of the red, orange and yellow light is affected by the air. However, much of the shorter wavelength light is absorbed by the gas molecules. The absorbed blue light is then radiated in different directions. It gets scattered all around the sky. Whichever direction you look, some of this scattered blue light reaches you. Since you see the blue light from everywhere overhead, the sky looks blue.