MENÚ CONTROL PATRIMONIAL
1) Relación de Bienes Muebles Controlados
PUTTING IT TOGETHER:
Review for Chapters 1–4
Multiple Choice
Choose the correct answer to each of the following.
1. 1.00 cm is equal to how many meters? 4. The number 0.0048 contains how many significant figures?
(a) 1 (b) 2 (c) 3 (d) 4
5. Express 0.00382 in scientific notation.
(a) 3.82 * 103 (c) 3.82 * 10-2 volume of the block is
(a) 4.01 mL (c) 22.2 mL (b) 0.249 mL (d) 2.49 mL
10. The density of copper is 8.92 g/mL. The mass of a piece of copper that has a volume of 9.5 mL is
(a) 2.6 g (c) 0.94 g
(b) 85 g (d) 1.1 g
11. An empty graduated cylinder has a mass of 54.772 g. When filled with 50.0 mL of an unknown liquid, it has a mass of 101.074 g. The density of the liquid is
(a) 0.926 g>mL (c) 2.02 g>mL (b) 1.08 g>mL (d) 1.85 g>mL
12. The conversion factor to change grams to milligrams is (a) 100 mg
13. What Fahrenheit temperature is twice the Celsius temperature?
(a) 64°F (c) 200°F
(b) 320°F (d) 546°F
14. A gold alloy has a density of 12.41 g>mL and contains 75.0% gold by mass. The volume of this alloy that can be made from 255 g of pure gold is
(a) 4.22 * 103 mL (c) 27.4 mL (b) 2.37 * 103 mL (d) 20.5 mL
15. A lead cylinder (V = r2h) has radius 12.0 cm and length 44.0 cm and a density of 11.4 g/mL. The mass of the cylinder is
(a) 2.27 * 105 g (c) 1.78 * 103 g (b) 1.89 * 105 g (d) 3.50 * 105 g 16. The following units can all be used for density except
(a) g>cm3 (b) kg>m3 (c) g>L (d) kg>m2 17. 37.4 cm * 2.2 cm equals
(a) 82.28 cm2 (c) 82 cm2 (b) 82.3 cm2 (d) 82.2 cm2
18. The following elements are among the five most abundant by mass in the Earth’s crust, seawater, and atmosphere except
(a) oxygen (c) silicon (b) hydrogen (d) aluminum 19. Which of the following is a compound?
(a) lead (c) potassium
(b) wood (d) water
20. Which of the following is a mixture?
(a) water (c) wood
(b) chromium (d) sulfur
21. How many atoms are represented in the formula Na2CrO4?
(a) 3 (b) (5) (c) (7) (d) 8
22. Which of the following is a characteristic of metals?
(a) ductile (c) extremely strong (b) easily shattered (d) dull
23. Which of the following is a characteristic of nonmetals?
(a) always a gas
(b) poor conductor of electricity (c) shiny
(d) combines only with metals
24. When a pure substance was analyzed, it was found to contain car-bon and chlorine. This substance must be classified as
(a) an element (b) a mixture (c) a compound
(d) both a mixture and a compound
25. Chromium, fluorine, and magnesium have the symbols (a) Ch, F, Ma (c) Cr, F, Mg
(b) Cr, Fl, Mg (d) Cr, F, Ma 26. Sodium, carbon, and sulfur have the symbols
(a) Na, C, S (c) Na, Ca, Su (b) So, C, Su (d) So, Ca, Su 27. Coffee is an example of
(a) an element (c) a homogeneous mixture (b) a compound (d) a heterogeneous mixture 28. The number of oxygen atoms in Al(C2H3O2)3 is
(a) 2 (b) 3 (c) 5 (d) 6
29. Which of the following is a mixture?
(a) water (c) sugar solution (b) iron(II) oxide (d) iodine
Answers for Putting It Together Reviews are found in Appendix VII.
79
80 Putting It Together
30. Which is the most compact state of matter?
(a) solid (c) gas
(b) liquid (d) amorphous
31. Which is not characteristic of a solution?
(a) a homogeneous mixture (b) a heterogeneous mixture
(c) one that has two or more substances (d) one that has a variable composition 32. A chemical formula is a combination of
(a) symbols (c) elements
(b) atoms (d) compounds
33. The number of nonmetal atoms in Al2(SO3)3 is
(a) 5 (b) 7 (c) 12 (d) 14
34. Which of the following is not a physical property?
(a) boiling point (c) bleaching action (b) physical state (d) color
35. Which of the following is a physical change?
(a) A piece of sulfur is burned.
(b) A firecracker explodes.
(c) A rubber band is stretched.
(d) A nail rusts.
36. Which of the following is a chemical change?
(a) Water evaporates.
(b) Ice melts.
(c) Rocks are ground to sand.
(d) A penny tarnishes.
37. The changing of liquid water to ice is known as a (a) chemical change
(b) heterogeneous change (c) homogeneous change (d) physical change
38. Which of the following does not represent a chemical change?
(a) heating of copper in air (b) combustion of gasoline (c) cooling of red-hot iron (d) digestion of food
39. Heating 30. g of water from 20.°C to 50.°C requires (a) 30. cal (c) 3.8 * 103 J (b) 50. cal (d) 6.3 * 103 J
40. The specific heat of aluminum is 0.900 J>g°C. How many joules of energy are required to raise the temperature of 20.0 g of Al from 10.0°C to 15.0°C?
(a) 79 J (b) 90. J (c) 100. J (d) 112 J 41. A 100.-g iron ball (specific heat = 0.473 J>g°C) is heated to
125°C and is placed in a calorimeter holding 200. g of water at 25.0°C. What will be the highest temperature reached by the water?
(a) 43.7°C (c) 65.3°C
(b) 30.4°C (d) 35.4°C
42. Which has the highest specific heat?
(a) ice (b) lead (c) water (d) aluminum 43. When 20.0 g of mercury are heated from 10.0°C to 20.0°C, 27.6 J
of energy are absorbed. What is the specific heat of mercury?
(a) 0.726 J>g°C (c) 2.76 J>g°C
(b) 0.138 J>g°C (d) no correct answer given 44. Changing hydrogen and oxygen into water is a
(a) physical change (b) chemical change (c) conservation reaction (d) no correct answer given
Free Response Questions
Answer each of the following. Be sure to include your work and expla-nations in a clear, logical form.
1. You decide to go sailing in the tropics with some friends. Once there, you listen to the marine forecast, which predicts in-shore wave heights of 1.5 m, offshore wave heights of 4 m, and tempera-ture of 27°C. Your friend the captain is unfamiliar with the metric system, and he needs to know whether it is safe for your small boat and if it will be warm. He asks you to convert the measurements to feet and degrees Fahrenheit, respectively.
2. Jane is melting butter in a copper pot on the stove. If she knows how much heat her stove releases per minute, what other mea-surements does she need to determine how much heat the butter absorbed? She assumes that the stove does not lose any heat to the surroundings.
3. Julius decided to heat 75 g CaCO3 to determine how much carbon dioxide is produced. (Note: When CaCO3 is heated, it produces CaO and carbon dioxide.) He collected the carbon dioxide in a bal-loon. Julius found the mass of the CaO remaining was 42 g. If 44 g of carbon dioxide take up 24 dm3 of space, how many liters of gas were trapped in the balloon?
Use these pictures to answer Question 4.
(1) (2) (3) (4)
(1) (2) (3) (4)
4. (a) Which picture best describes a homogeneous mixture?
(b) How would you classify the contents of the other containers?
(c) Which picture contains a compound? Explain how you made your choice.
Use these pictures to answer Question 5.
5. (a) Which picture best represents fluorine gas? Why?
(b) Which other elements could that picture also represent?
(c) Which of the pictures could represent SO3 gas?
6. Sue and Tim each left a one-quart bowl outside one night. Sue’s bowl was full of water and covered, while Tim’s was empty and open. The next day there was a huge snowstorm that filled Tim’s bowl with snow. The temperature that night went down to 12°F.
(a) Which bowl would require less energy to bring its contents to room temperature (25°C)? Why?
(b) What temperature change (°C) is required to warm the bowls to 25°C?
(c) How much heat (in kJ) is required to raise the temperature of the contents of Sue’s bowl to 0°C (without converting the ice to water)?
(d) Did the water in Sue’s bowl undergo chemical or physical changes or both?
Putting It Together 81 7. One cup of Raisin Bran provides 60.% of the U.S. recommended
daily allowance (RDA) of iron.
(a) If the cereal provides 11 mg of iron, what is the U.S. RDA for Fe?
(b) When the iron in the cereal is extracted, it is found to be the pure element. What is the volume of iron in a cup of the cereal?
8. Absent-minded Alfred put down a bottle containing silver on the table. When he went to retrieve it, he realized he had forgotten to label the bottle. Unfortunately, there were two full bottles of the same size side-by-side. Alfred realized he had placed a bottle of mercury on the same table last week. State two ways Alfred can determine which bottle contains silver without opening the bottles.
9. Suppose 25 g of solid sulfur and 35 g of oxygen gas are placed in a sealed container.
(a) Does the container hold a mixture or a compound?
(b) After heating, the container was weighed. From a comparison of the total mass before heating to the total mass after heating, can you tell whether a reaction took place? Explain.
(c) After the container is heated, all the contents are gaseous. Has the density of the container including its contents changed? Explain.
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P
ure substances are classified as elements or compounds, but just what makes a substance possess its unique properties? How small a piece of salt will still taste salty?Carbon dioxide puts out fires, is used by plants to produce oxygen, and forms dry ice when solidified. But how small a mass of this material still behaves like carbon dioxide? Substances are in their simplest identifiable form at the atomic, ionic, or molecular level. Further division produces a loss of characteristic properties.
What particles lie within an atom or ion? How are these tiny particles alike? How do they differ? How far can we continue to divide them? Alchemists began the quest, early chemists laid the foundation, and modern chemists continue to build and expand on models of the atom.
5.1 Dalton’s Model of the Atom 5.2 Electric Charge
5.3 Subatomic Parts of the Atom 5.4 The Nuclear Atom
5.5 Isotopes of the Elements 5.6 Atomic Mass