Matching: Place the letter that best defines the numbered term in the correct place on your answer sheet. (5 points)
A. atom 1. a change that does not produce a new substance
B. chemical change 2. a reaction that releases energy
C. endothermic 3. a reaction that absorbs energy
D. exothermic 4. a change that produces new substances
E. physical change 5. the smallest part of an element that is still an element and does not change in a
chemical reaction
A. electron 6. substance whose atoms are close together and do not move around easily
B. gas 7. a positively charged atomic particle
C. liquid 8. a substance whose atoms tend to move farther apart
D. proton 9. a substance whose atoms are quite far apart and move around freely
E. solid 10. a negatively charged atomic particle
Multiple Choice: Read each question or statement. Place your answer on the answer sheet. (2 points)
11. Which of the following is a chemical change and not a physical change?
A. melting an ice cube B. gasoline from a carŐs tank evaporating from a garage floor C. tearing a piece of paper in half D. burning paper to form water vapor, ashes, and carbon dioxide
12. Keisha is studying an unknown substance. Using a powerful microscope, she notices that its particles are very close together and do not move. The substance has a definite shape. From her data, Keisha can conclude that her unknown substance is A. plasma B. a gas C. a liquid D. a solid
13. Francisco read a book about a visit to a bakery. In the book, the author mentioned that when a cake bakes, the heat changes water in the batter to water vapor. Francisco knows this is what type of change?
A. color change B. precipitate change C. chemical change D. physical change
14. Janie cleaned out the freezer part of the refrigerator. She found a carton of ice cream. She forgot to put it back when sheŐd finished cleaning. What happened to the particles in the ice cream?
A. A decrease in temperature caused them to move closer together B. A decrease in temperature caused them to move farther apart C. An increase in temperature caused them to move closer together
D. An increase in temperature caused them to move farther apart
15. James saw the graph below in his text book. Which letter shows the boiling of water to form water vapor gas?
****(Note: Graph does not appear in this format, you must consult your original exam to see the graph) ****
16. When atoms join together, they form A. molecules B. elements C. atoms D. particles
17. Which is true of atoms in a chemical reaction A. they do not change B. they change
C. they become something new D. they release heat, light, or electricity
18. Which of the following makes up an atom?
A. protons, electrons, and neutrons B. only protons C. only electrons D. only neutrons
19. Which particle in an atom has a positive charge? A. protons B. neutrons C. electrons
D. all of the above
20. Which particle in an atom has a negative charge? A. electrons B. neutrons C. protons
D. all of the above
Reading and Interpreting: Read the following passage and answer the questions. (2 points)
You probably see fireworks every Fourth of July. Have you ever wondered how the dazzling colors
and thunderous sounds of fireworks are made? They are carefully controlled exothermic reactions. Safety is a major concern in making fireworks.
Modern fireworks are shells launched from tubes on the ground. A fast-burning fuse kindles a charge of black powder that propels the shell skyward. When the shell is high in the air, a slower-burning fuse kindles other compartments filled with flash powder. Pellets inside these charges produce colors. Usually, another charge explodes in a final big bang.
Making fireworks is both a science and an art. It requires a great deal of knowledge of chemistry. Each color, for example, is the result of a certain mixture of elements or compounds in the pellets. Green stars
come from barium compounds, red from strontium, and blue from copper. Because the color-producing compounds arenŐt very stable, they must be created during the explosion of the charge. Making the right chemical reactions occur in the correct way is one of the biggest challenges of building fireworks.
Each pattern you see when a fireworks shell explodes is the result of a different arrangement of the color-producing pellets inside the flash-powder charges. A fireworks company carefully guards its secret "recipes" for packing its fireworks shells.
21. According to the article A. heat is released during a fireworks explosion B. heat is absorbed
during a fireworks explosion C. heat is neither released nor absorbed during a fireworks explosion
D. heat is both released and absorbed during a firework explosion
22. According to the article, why are the color producing compounds created during the explosion?
A. they arenŐt very stable B. they are dangerous if mixed beforehand C. they only form colors
when they are mixed D. they arenŐt produced during the explosion but are always present
23. In the passage, what is meant by the word kindles? A. ignites B. puts out C. extinguishes D. smothers
24. Why do you think the author refers to the packing of the firework shells as ŇrecipesÓ:
A. it takes several ingredients in differing amounts to make the right firework B. the fireworks
are cooked like food C. fireworks are made in kitchens D. fireworks are made from edible substances
25. What does the article attempt to explain? A. the chemical reactions in fireworks
B. why fireworks are so loud C. how to make your own fireworks D. the danger in making fireworks