Name: Class: Date: Topics in Chemistry Final Exam Study Guide

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1 Name: Class: _ Date: _ Topics in Chemistry Final Exam Study Guide Multiple Choice Identify the choice that best completes the statement or answers the question. 1. If the force applied to an object increases, how is the pressure affected? Assume constant area. a. The pressure will decrease c. The pressure will remain the same b. The pressure will increase 2. When an inverted glass jar is lowered into a container of water, the water does not enter the jar. This demonstration shows that air a. has mass. c. is a mixture of gases. b. has high solubility in water. d. takes up space. 3. Standard atmospheric pressure can be expressed as a. 100 mmhg c. 760 mmhg b. 100 atmospheres d. 760 atmospheres 4. What is the SI unit for force? a. Newton c. Kelvin b. Joule d. Pascal 5. The constant bombardment of the walls of a container by the moving molecules of a gas produces the property of gases called a. temperature c. pressure b. density d. diffusion 6. Which quantity is not equal to one atmosphere of pressure? a. 760 mmhg c. 34 feet of water b kpa d liters air 7. Which formula is correct for calculating pressure? a. P = force + area c. P = b. P = d. P = force x area 8. What piece of equipment is used to measure atmospheric pressure? a. thermometer c. barometer b. hydrometer d. sling psychrometer 9. Calculate the pressure in kilopascals exerted by a textbook on the desk. The dimensions of the textbook are 24.0 cm 18.0 cm and the force it exerts is 3.00 Newtons. a kpa c kpa b kpa d kpa 10. Which term best describes the relationship between pressure and volume of a gas? a. inverse c. complimentary b. direct d. indirect 1

2 Name: 11. A cylinder with a movable piston holds 352 ml of nitrogen gas at a pressure of 791 mm Hg. By moving the piston, at what volume would be the pressure equal 649 mm Hg? (assume constant temperature) a. 288 ml c ml b. 429 ml d ml 12. If temperature is held constant, decreasing the volume of a sample of gas will cause its pressure to a. decrease c. remain the same b. increase 13. One way to increase the volume of the gas in a flexible container is to a. lower the temperature of the gas b. increase the pressure on the outside walls of the container c. replace the gas with another of higher molecular mass d. decrease the pressure on the outside walls of the container 14. At a pressure of 800 mmhg, a sample of oxygen occupies 400 ml. If the temperature is held constant, what is the volume that the gas will occupy if the pressure decreases to 400 mmhg? a. 200 ml c ml b. 800 ml d ml 15. A sample of gas has a volume of 3.75 L and a pressure of 775 mm Hg. At what volume will the pressure be 675 mm Hg? (Assume temperature is constant.) a L c L b L d L 16. If oxygen gas occupies 251 ml at 729 mm Hg, at what volume will its pressure be 753 mm Hg? (Assume temperature is constant.) a. 219 ml c. 257 ml b. 243 ml d. 269 ml 17. When air is removed from a bell jar with a vacuum pump the pressure in the bell jar is reduced at constant temperature. What happens to a sealed, inflated balloon inside the bell jar? a. gets smaller c. stays the same size b. gets larger 18. A sample of argon gas occupies a volume of 250. ml at 740. mm Hg pressure. At what volume will its pressure be 800. mm Hg? (assume the temperature is constant) a. 231 ml c. 462 ml b ml d ml 19. A balloon filled with air with a volume of 1.0L sits at room temperature. Liquid nitrogen is poured over the balloon and it shrinks to a volume of 0.25L. At what temperature is the liquid nitrogen? a. Same as room temperature c. Greater than room temperature b. Lower than room temperature 20. Which term best describes the relationship between temperature and volume? a. inverse c. complimentary b. direct d. indirect 21. If the pressure of one mole of gas remains constant while the temperature increases, then the volume will a. decrease c. remain constant b. increase 2

3 Name: 22. A temperature of 373 K is equal to what temperature on the Celsius scale? a. 0 C c. 373 C b. 100 C d. 646 C 23. A 30.0-mL sample of a gas is collected at 100. K. What volume will it occupy at 300. K? (assume constant pressure) a ml c ml b ml d ml 24. A 90-mL sample of hydrogen gas is collected at a temperature of 27 C, how many milliliters will the hydrogen occupy at 42 C? (assume constant pressure) a. 58 ml c. 95 ml b. 86 ml d. 140 ml 25. What is the appropriate temperature scale for solving problems using Charles' law? a. Celsius c. Fahrenheit b. Centigrade d. Kelvin 26. Which value represents the temperature, absolute zero? a. 0 C c. 273 C b. 0 K d. 273 K 27. Which temperature is equal to 46 C? a. 46 K c. 273 K b. 227 K d. 319 K 28. If the volume of a gas at 28 C increases from 15 ml to 25 ml at constant pressure, what is the new temperature? a. 230 C c. 47 C b. 180 C d. 17 C 29. If a gas occupies 200 ml at 400 K, what volume will it occupy at 250 K? (assume constant pressure) a. 125 ml c. 450 ml b. 320 ml d. 500 ml 30. To convert a temperature in Celsius to Kelvin, which is the correct operation? a. add 273 c. multiply by 273 b. subtract 273 d. divide by What is the final volume of a gas at 525 C, if the gas originally occupied 320 ml at 38 C? Assume that pressure is constant. a. 23 ml c ml b. 125 ml d. 820 ml 32. A gas has a pressure of 801 mmhg at 349 K. If the pressure is reduced to 701 mmhg, what is the new temperature? (Assume the volume is constant.) a. 250 K c. 399 K b. 305 K d. 802 K 33. A sample of gas in a fixed volume container at kpa is heated from 20 C to 227 c. What will be the pressure at 500 K? a kpa c kpa b. 173 kpa d kpa 34. The average kinetic energy of gas molecules increases with a. a decrease in pressure c. an increase in temperature b. an increase in volume d. an increase in density 3

4 Name: 35. As the average kinetic energy of the molecules of a sample increases, the temperature of the sample a. decreases c. remains the same b. increases 36. What is the volume of one mole of the ideal gas at STP? a L c L b L d L 37. At STP the volume of a sample of gas is 75 ml. At 2 C and 1.0 atm, the volume of the gas sample will be a. 69 ml c ml b. 81 ml d ml 38. As a 25 L weather balloon rises in the atmosphere, the pressure on it drops from 750 mmhg to 500 mmhg. The temperature also decreases from 298 K to 229 K. What is the volume of the balloon under these new conditions? a. 49 L c. 29 L b. 22 L d. 13 L 39. What is the volume occupied by 10.0 moles of argon at 27.0 C and mm Hg? a L c. 253 L b L d. 268 L 40. Deposition occurs when a a. solid turns into a liquid. c. solid turns into a gas. b. liquid turns into a solid. d. gas turns into a solid. 41. What phase change occurs during sublimation? a. gas solid c. gas liquid b. solid gas d. liquid gas 42. Hydrocarbons are compounds that contain a. oxygen and carbon atoms c. carbon, hydrogen, and nitrogen atoms b. hydrogen and carbon atoms d. carbon, oxygen, and nitrogen atoms 43. Which of the following would have a high viscosity a. water c. coffee b. milk d. honey 44. Which of the following would have a low viscosity? a. Honey c. Paraffin wax b. Mineral Oil d. Water 45. A student wrote down that one of the petroleum samples flows slowly, is thick and syrupy and jet-black in color. You can conclude that this petroleum sample has a a. high viscosity b. low viscosity c. no viscosity d. not enough information to make a claim about the samples viscosity 46. Which statement is true about petroleum resources and use? a. The United States consumes more petroleum than it produces. b. Petroleum reserves are uniformly distributed throughout the world. c. Petroleum is used much more for building new products than as a fuel source. d. The use of petroleum is decreasing at a rapid rate. 4

5 Name: 47. At what level in a fractionating tower would you expect to remove the fraction with the highest boiling point? a. Top c. Bottom b. Middle 48. Water and butanol can be separated by distillation due to their differences in a. molecular formulas c. boiling points b. colors d. specific gravity 49. Fractional distillation is based on the fact that substances found in crude oil a. have different boiling points c. burn in oxygen b. are used in petrochemicals d. are less dense than water 50. Alkanes are hydrocarbons with one or more carbon-carbon bond. a. single c. triple b. double d. quadruple 51. What is the formula of an alkane with 16 carbons? a. C 16 H 32 c. C 32 H 16 b. C 16 H 34 d. C 16 H An unbranched alkane containing six carbon atoms is named a. 6-methane c. hexane b. hexide d. methylhexane 53. The chemical name for C 3 H 8 is a. butane c. propane b. pentane d. ethane 54. The saturated hydrocarbon with seven carbons is named a. propane c. heptane b. hexane d. nonane 55. The correct formula for pentane is a. C 5 H 10 c. C 9 H 20 b. C 7 H 14 d. C 5 H How many carbon atoms are found in a decane molecule? a. 10 c. 8 b. 2 d Which structural formula represents propane? a. c. b. d. 5

6 Name: 58. Isomers are different compounds that have a. molecules with the same arrangement but are made of different elements b. molecules with the same molecular formula but different structural formulas c. the same empirical formula but different molecular formulas d. the same structural formula but different physical properties 59. How many isomers does pentane have? a. 3 c. 5 b. 4 d How many isomers are possible for butane? a. one c. three b. two d. four 61. Compounds that have the same molecular formula but different structural formulas are called? a. isotopes c. allotropes b. isomers d. homologs 62. Which compound has the lowest boiling point? a. CH 4 c. C 5 H 12 b. C 3 H 8 d. C 7 H All organic compounds contain the element a. carbon c. oxygen b. hydrogen d. nitrogen 64. Ice floats in water because a. ice is more dense than water c. water and ice have the same density b. water is more dense than ice 65. Water-based solutions are called a. aqueous solutions c. electronegativity b. mixtures d. homogenous solutions 66. The dissolved substance in a solution is the a. solvent c. precipitate b. solute d. filtrate 67. A molecule that is positively charged on one end and negatively charged on the other end is called a a. polar molecule. c. nonpolar molecule. b. magnetic molecule. d. balanced molecule. 68. Which two liquids will dissolve in each other? a. ethanol and water c. motor oil and rain water b. salad oil and vinegar d. vegetable oil and water 69. Sodium chloride is held together by bonds which result from a. shared electrons. c. the same number of protons. b. attraction of ions. d. the same number of electrons. 70. A polar substance has a. an asymmetrical distribution of charge. b. a symmetrical distribution of charge. c. negative charges, only. d. positive charges, only. 6

7 Name: 71. A sample of sugar is added to enough water for all the sugar to dissolve. The sugar is said to be in water. a. soluble c. slightly soluble b. insoluble d. suspended 72. In the following reaction what does (s) stand for? MgCl 2 (s) Mg 2+ (aq) + 2Cl - (aq) a. Soluble c. Solution b. Saturated d. Solid 73. A solution in which more solute can be dissolved at a certain temperature is a. saturated. c. supersaturated. b. unsaturated. 74. You are given 100 grams of a 25% sugar solution by mass. This solution contains a. 25 grams of sugar and 75 grams of water. b. 25 grams of sugar and 100 grams of water. c. 75 grams of sugar and 25 grams of water. d. 100 grams of sugar and 25 grams of water. 75. Molarity is one method used to express a. relative mass. c. gas density. b. solution concentration. d. compound composition. 76. Generally, for solids dissolving in liquids, how does an increase in temperature affect the solubility of a solid? a. decreases solubility c. does not affect solubility b. increases solubility d. affects the solubility unpredictably 77. A solution that has less than the maximum amount of solute that can dissolve at a given temperature is called a. saturated. c. supersaturated. b. unsaturated. 78. A saturated solution of NaNO 3 can be made unsaturated by a. decreasing the temperature of the solution. b. increasing the temperature of the solution. c. removing water from the solution. d. stirring the solution. 79. You have 550. ml of a 1.50 M KNO 3 solution. Calculate the new concentration when 75.0 ml of this solution is diluted to a total volume of 100. ml. a M c M b M d M 7

8 Name: Figure 4B (Use Figure 4B-2.) What is the mass of KCl needed to make a saturated solution in 100 g of water at 50 C? a. 33 g b. 43 g c. 50. G d. 72 g e. 82 g 81. (Use Figure 4B-2.) At what temperature will 130 g of KNO 3 dissolve in 100 grams of water to produce a saturated solution? a. 21 C b. 27 C c. 68 C d. 72 C e. 90 C 8

9 Name: Figure 4B (Use Figure 4B-3.) How many grams of KNO 3 will dissolve in 100 grams of water at 50 o C? a. 50 g c. 77 g b. 62 g d. 84 g 83. (Use Figure 4B-3.) A solution contains 22 grams of KCl at 30 o c. What is the minimum number of additional grams of KCl that can be dissolved for the solution to be just saturated? a. 14 g c. 36 g b. 22 g d. 48 g 84. (Use Figure 4B-3.) A solution that contains 50. grams of NH 4 Cl in 100 grams of water at 40 o C is a. unsaturated. c. supersaturated. b. saturated. 85. Which statement best describes a precipitate formed in an aqueous chemical reaction? a. A substance that leaves the reaction container as a gas. b. A substance that settles to the bottom of the container as a solid. c. It is the product that has a neutral charge. d. It is the product that causes the solution to change color. 86. Which compound is classified as a base? a. NaOH c. HNO 3 b. MgCl 2 d. CH 4 9

10 Name: 87. Which symbol represents a hydronium ion? a. OH - c. H 3 O + b. H 2 O d. H Which symbol represents a hydroxide ion? a. OH - c. H 3 O + b. H 2 O d. H A pond is contaminated with a chemical that is a base. Which ion will be present in higher concentration than in uncontaminated water? a. H + b. OH - c. Cd 2+ d. SO 2-4 e. Ba Vinegar contains a water solution of acetic acid. The most likely ph of vinegar is a. -1 c. 3 b. 7 d The ph scale measures the a. solubility of a substance. c. amount of indicator in a solution. b. amount of chlorine ions in a solution. d. acidity level of a solution. 92. Which substance will produce a solution with a basic ph when dissolved in water? a. HCl c. CO 2 b. Sugar d. NaOH 93. Which ph value indicates a basic solution? a. 2 c. 7 b. 4 d. 10 Short Answer 94. Explain, in terms of air pressure, how a suction cup with a hook can support the weight of a small object. 95. As you dive deeper into water, the water pressure increases. This pressure is much greater than atmospheric pressure, which our lungs are made for. Explain, in terms of Boyle s law, what would happen to our lungs if we were to swim at great depths underwater. 10

11 Name: 96. Using gas laws, explain why you should not throw a can filled with a gas into a fire. 97. What is the volume of a gas at standard pressure if the volume at mmhg is 675 ml? Assume constant temperature. 98. A gas occupies a volume of 185 ml at 250. K. What volume will it occupy at 300 K? Assume constant pressure. 99. Explain, in terms of temperature, volume, and pressure, why a balloon should not be inflated completely in an air-conditioned store because it will probably burst if taken out into the heat Explain, in terms of temperature, volume, and density why warm air rises while cool air falls causing the turning over of the troposphere A rigid gas cylinder with a volume of 42 liters is filled with propane gas at 33 C and has a pressure of 4.0 atmospheres. Calculate the number of moles of propane in the cylinder. Show all work. 11

12 Name: 102. Calculate the number of moles of methane in a 44.0-liter cylinder at 1.20 atmospheres and 302 K. Show all work List eight items in the classroom that were made from petroleum products or that required the consumption of petroleum as they were manufactured Describe two major problems posed by our present use of petroleum energy sources Write the molecular formula for the alkane that contains 28 carbon atoms Write the molecular formula for octane At what Celsius temperature can both the liquid and the solid phase of water be naturally present? 108. What is a nonpolar substance? 109. Explain why substances having polar molecules tend to dissolve in water. 12

13 Name: 110. Explain the phrase, "like dissolves like" in terms of particles What is the difference between an insoluble and soluble substance? 112. What does the symbol aq stand for in a chemical reaction? 113. Calculate the percent by mass of Ca(NO 3 ) 2 in a solution that contains 56 grams of the solute in 250 grams of water How many grams of CaCl 2 are there in g of solution that is 15.0% CaCl 2 by mass? 115. What is the percent by mass of sugar in a solution that has 132 grams of sugar is dissolved in 750 grams of water? 116. A student has a beaker holding 50.0 grams of a solution that contains 12 grams of NaCl. What is the percent NaCl by mass in this solution? 13

14 Name: PART III Match the letter on the diagram with the term for that point or region Vapor 118. Normal freezing point 119. Triple point 120. Solid 121. Normal boiling point 122. Liquid 14