Physical Science- nuclear fission, bonds

1. wA refrigerator causes a transfer of thermal energy from a cooler region to a hotter region. The separation of hot and cold causes an increase in order. The following two questions deal with this situation.
2. If the refrigerator door was left open, what happens to the temperature in the room? Explain your answer using the Law of Increasing Disorder.
3. If the fridge door were shut, order would appear to increase with the separation of hot and cold. Explain how this is possible using the Law of Increasing Disorder.
4. For the following six questions, consider nuclear fusion and nuclear fission.
5. As an energy source, what are some of the drawbacks and advantages of fission?
6. As an energy source, what are some of the drawbacks and advantages of fusion?
7. Why is fusion generally considered a preferable energy source over fission?
8. Why are all commercial nuclear power plants using energy from fission instead of energy from fusion?
9. How does the mass of the heavy nucleus and neutron compare with the mass of the fission products (including the neutrons)?
10. How does the total mass of the lighter nuclei at the start of the fusion process compare to the combined mass of the heavier nucleus formed at the end of the fusion process and the neutron released?

III. For two of the following three questions, you will need to create your own diagrams. You may draw them on paper and scan the images or create them directly in a graphics program (such as PowerPoint, Paint, and so on).When you have the electronic copy of your diagram, select the diagram (in Paint, PowerPoint, or whatever program you used), press Ctrl+C to copy it.Place your cursor in the text area for the question, and press Ctrl+V to paste in your image.

9. Here are the ball-and-stick diagrams for acetic acid, ammonia, and oleic acid (olive oil).
10. Draw the arrangement of ions in a salt and paste your diagram into the text area. What forces hold these network solids together? Explain the difference between polar molecules and ionically bound material.
11. Rank the following in order of least strong to most strong: dispersion forces, ionic bonds, dipole-dipole interactions, covalent bonds, nuclear bonds (over distances inside the nucleus of an atom), hydrogen bonds.
12. For the next three questions, use this information. In the course, you saw demonstrations for several chemical reactions: (1) hydrogen combining with oxygen to make water; (2) iron oxide combining with aluminum to make iron and aluminum oxide (the thermite reaction); (3) water being broken into hydrogen and oxygen through electrolysis; and (4) hydrogen and oxygen combining using a palladium catalyst.

This video shows one more, baking soda and vinegar forming carbon dioxide and sodium acetate solution.

12. Sketch a graph of the potential energy surfaces similar to figure 20.4 or figure 20.7 in your textbook showing changes in energy for eachof the reactions. This means you will have five graphs or one graph with five different lines. You don’t need to draw the pictures of the molecules that are shown on Figure 20.4 or 20.7 unless that is helpful to you. These drawings just need to show the general idea of what is happening in the reaction; they do not have to be quantitatively exact.
13. Which Of the five reactions described above are energetically favorable? Explain why.
14. What values complete the following chemical equations so that they are balanced?
15. ____ H₂+ O₂= 2H₂O
16. 2Fe₂O₃+ ____Al = 2Al₂O₃+ _____Fe
17. NaHCO₃+ CH₃COOH = NaH₂CCOOH + H₂O + _____CO₂
18. Use this information for the following three questions.

These are the mass spectra for formic acid, HCOOH, and acetic acid, CH₃COOH. Both of these came from the NIST Chemistry WebBook (http://webbook.nist.gov/chemistry).

Graph A:

Graph B:

15. Complete the table for each of the molecules.

16. Which graph is for which molecule?
17. Draw each molecule and circle the fragments that could be responsible for the three largest peaks on each spectrum.
18. For the next four questions, consider a compound of magnesium and chlorine held together by ionic bonds.
19. Determine the oxidation states of magnesium and chlorine.
20. Write the chemical formula for the compound.
21. Sketch an energy well (that is, energy level diagram for the quantum mechanical model of the atom) for each kind of atom in the compound. Draw a circle around each electron to be given up by one atom in forming the compound and also an empty circle at each location where the other atom will put an electron in forming the compound.
22. What properties would you expect for magnesium chloride? Explain why these properties occur.

VII. For the next four questions, consider the chemical reaction in which magnesium burns in oxygen to form magnesium oxide.

22. Write and balance the chemical equation representing the reaction.
23. Explain why a match was needed to start the reaction.
24. Describe what happens to the energy within the system as the products are formed. What changes in the forms of energy occur?
25. Describe what happens to the disorder of the universe as the products are formed.

VIII. For the next three questions, consider the behavior of electrons in covalent, metallic, and ionic bonds.

26. Copy this table into the text area. Put an X to mark which bonds have the following electron characteristics.

27. Which of the characteristics listed above helps a substance dissolve in polar substances such as water? Explain why.
28. Which of the characteristics listed above makes it possible for a substance conduct electricity and be shiny? Explain why.