December 17, 2001

Part I-- Short Answers

75 points (as marked)

Fill in the missing word, number or term-- 2.5 points per item (50 points total)

1. Atmospheric pressure __ decreases____ as the altitude increases.

2. Humidity is another name for ___water ---vapor__ in the atmosphere.

3. The air layer closest to the earth is called the __t roposphere___.

4, 5. The name of the species KNO₃ is _potassium_ __nitrate_. (2 words)

6. An aqueous solution will always contain __ water__.

7. A chemical reaction that produces heat is said to be __exothermic__.

8. Light energy is said to be quantized, in little bundles of energy called _photons__.

9. CFC or freon is a gas, formerly used in refrigerators, but banned because of concern for the ozone layer

10. __ Distillation___ is a separation process in which a solution is heated to boiling and the vapors are condensed and collected.

11. A __ catalyst__ is a species that increases the speed of a chemical reaction but is not used up in the reaction.

12. Gasoline contains a hydrocarbon with 8 carbons known as _octane (isooctane is ok)___.

13. _ Electronegativity__ is a measure of an atom's attraction for the electrons

it shares in a covalent bond.

14. A base is a chemical compound that produces __OH- or hydroxyl ions_ in water.

15. Chernobyl is a city in the Ukraine best known for

nuclear accident, meltdown, escape of nuclear materials (brief answer ok)

16. The government agency that regulates air and water quality is

__EPA=environmental protection agency__ name, not just abbreviation

17. The government agency that approves new drugs is

FDA=Food and Drug Administration name, not just abbreviation

18., 19 Pure Carbon exists in three well defined atomic forms: name two

_diamond, graphite_ and _(buckeyballs, fullrences, C60, buckmisterfullerene)__________ (coal is not acceptable; charcoal partial credit)

(accepting C12 and C14 isotopes. Although that's not what I intended it's a legitimate reading of the question.

20. One early form of plastics was made by modifying a naturally occurring polymer. This plastic was called ___rayon, nitrocellulose, celluloid ___(there are several acceptable answers).

------------------------short answers (5 pts each; answer 5 of 6 questions)------------------------------

21 (5 points) How much heat is released when 1 mole of H₂ reacts with F₂?

data: bond energy of H₂ is 432 kJ/mol, of F₂ is 155 kJ/mol and for HF is 565 kJ/mol

• H2 + F2 --> 2 HF
• bonds after:
  • 2 H-F = 2 x 565 = 1130 kJ
• bonds before
  • 1 H-H = 432
  • 1 F-F = 155
  • sum: 587 corrected from first posting
• difference = 1130-587 =543 k Joules

solar panels, geothermal, nuclear, hydroelectric, use of hydrogen as fuel, sunlight, batteries

and then using the Hydrogen and Oxygen as fuel to run an electrical power plant. What's

wrong with this idea as a way of making energy?

Net energy production is zero if ideal, a clear loss if generator, etc. is not perfect (and they never are.) Costs as much energy to decompose water as you get back in compbustion. It is, after all, the reverse reaction.

Some waste is reprocessed, especially in europe. In US little is reprocessed. In either event some or all of the spent fuel must be stored, away from people, for long periods of time. The US has been unable to develp long term stroage, so most of the waste is stored on site at nuclear power plants.

mark here ____ and write on the back of this page; cross off the question you skipped

Draw three isomers of C₃H₅OH (or of C₃H₆O)

drawings, not posted to the Web site; need either C=O or a C=C to make count right

will need 4 bonds to a C, 2 to an O, 1 to a H