CHE 17 Name

Test 3

May 14, 1997

Multiple choice: (2 points each)

1. Which pair of compounds is associated with acid rain?

(a) H2SO4 and HNO3

(b) H2SO4 and HCl

(c) HNO3 and H3PO4

(d) H3PO4 and HCl

2. Which is not true about fusion?

(a) Very high temperatures are required.

(b) There is no readily available source of deuterium fuel.

(c) Fusion has fewer radioactive byproducts than fission.

(d) All of these statements are true.

3. Solar cells consist of

(a) pure silicon

(b) superconducting ceramics

(c) silicon containing arsenic and boron traces

(d) deuterium and tritium

4. Why is pure water neutral?

(a) Pure water has no H+ ions and no OH ions.

(b) Pure water has equal numbers of hydrogen and hydroxide ions.

(c) Pure water has no dissolved carbon dioxide.

(d) The pH of pure water at 25 oC is 7.

5. Gasoline is a

(a) single, simple hydrocarbon.

(b) single, complex hydrocarbon.

(c) mixture of C12-C16 hydrocarbons.

(d) mixture of C5-C12 hydrocarbons.

 

Short answer:

6. How is an octane rating determined? What structural factors influence octane ratings? (7 points)

 

 

 

 

 

 

7. What is necessary to have a buffer? How do buffers work? (7 points)

 

 

 

 

 

 

 

8. Why do organic chemists classify compounds according to their functional groups? (5 points)

 

 

 

 

 

 

9. Explain how an alcohol and an ether differ in structure and in properties. (5 points)

 

 

 

 

 

 

10. Which is more economical, to burn a fuel in your home and generate a certain amount of heat, or to burn the same amount of fuel in an electric power plant and use that energy in your home? Explain briefly. (5 points)

 

 

 

 

 

 

 

Problems: (Show your work for full credit.)

11. Determine the concentration (in units of molarity) of a 4685 mL solution containing 1.65 g HNO3. (6 points)

 

 

 

 

12. Determine the pH of the following solutions. (3 points each part)

(a) 0.0001 M HCl

 

(b) 0.00056 M NaOH

 

(c) pure water

 

13. Provide the products for the following reactions and balance the equations. (3 points each part)

(a) Mg(OH)2 + HCl

 

(b)

(c)

 

(d) CH3CO2H + NaOH

 

 

14. How much uranium must be reacted to release 1000 kcal of energy? Compare this amount of uranium to the amount of fossil fuel needed to release the same amount of energy. (10 points)

235U + 1n 141Ba + 92Kr + 3 1n + 4.6 x 109 kcal

 

 

 

 

 

 

 

 

 

Essay Questions. Write your answer in complete sentences using proper grammar. (12 points each)

15. What events led to the accident at the Three Mile Island nuclear power plant? Compare and contrast the Three Mile Island accident to the one at Chernobyl.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

16. Describe the three types of fossil fuels, and explain the advantages and disadvantages of each.