test 8 review

1. Radiant energy isA) the energy stored within the structural units of chemical substances.B) the energy associated with the random motion of atoms and molecules.C) solar energy, i.e. energy that comes from the sun.D) energy available by virtue of an object's position.Ans: C Category: Easy Section: 6.1

2. Thermal energy isA) the energy stored within the structural units of chemical substances.B) the energy associated with the random motion of atoms and molecules.C) solar energy, i.e. energy that comes from the sun.D) energy available by virtue of an object's position.Ans: B Category: Easy Section: 6.1

3. Chemical energy isA) the energy stored within the structural units of chemical substances.B) the energy associated with the random motion of atoms and molecules.C) solar energy, i.e. energy that comes from the sun.D) energy available by virtue of an object's position.Ans: A Category: Easy Section: 6.1

4. Potential energy isA) the energy stored within the structural units of chemical substances.B) the energy associated with the random motion of atoms and molecules.C) solar energy, i.e. energy that comes from the sun.D) energy available by virtue of an object's position.Ans: D Category: Easy Section: 6.1

5. Heat isA) a measure of temperature.B) a measure of the change in temperature.C) a measure of thermal energy.D) a measure of thermal energy transferred between two bodies at different

temperature.Ans: D Category: Medium Section: 6.2

6. An endothermic reaction causes the surroundings toA) warm up. D) decrease in temperature.B) become acidic. E) release CO2.C) condense.Ans: D Category: Easy Section: 6.2

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Chapter 6: Thermochemistry

7. An exothermic reaction causes the surroundings toA) warm up. D) decrease its temperature.B) become acidic. E) release CO2.C) expand.Ans: A Category: Easy Section: 6.2

8. Copper metal has a specific heat of 0.385 J/g·°C. Calculate the amount of heat required to raise the temperature of 22.8 g of Cu from 20.0°C to 875°C.A) 1.97 10–5 J B) 1.0 10–2 J C) 329 J D) 7.51 kJ E) 10.5 kJAns: D Category: Medium Section: 6.5

9. Calculate the amount of heat necessary to raise the temperature of 12.0 g of water from 15.4°C to 93.0°C. The specific heat of water = 4.18 J/g·°C.A) 0.027 J B) 324 J C) 389 J D) 931 J E) 3,890 JAns: E Category: Medium Section: 6.5

10. How much heat is required to raise the temperature of 2,500 g of water from 27°C to 72°C? The specific heat of water is 4.184 J/g·°C.A) 0.19 kJ B) 10. kJ C) 280 kJ D) 470 kJ E) 750 kJAns: D Category: Medium Section: 6.5

11. A beaker contains 115 g of ethanol at 18.2°C. If the ethanol absorbs 1125 J of heat without losing heat to the surroundings, what will be the final temperature of the ethanol? The specific heat of ethanol is 2.46 J/g°C.A) 4.08°C B) 14.1°C C) 18.4°C D) 22.2°C E) 36.4°CAns: D Category: Medium Section: 6.5

12. How many degrees of temperature rise will occur when a 25.0 g block of aluminum absorbs 10.0 kJ of heat? The specific heat of Al is 0.900 J/g·°C.A) 0.44°C B) 22.5°C C) 225°C D) 360°C E) 444°CAns: E Category: Medium Section: 6.5

13. If 325 g of water at 4.2°C absorbs 12.28 kJ, what is the final temperature of the water? The specific heat of water is 4.184 J/g·°C.A) 4.21°C B) 4.8°C C) 9.0°C D) 13.2°C E) 2,938°CAns: D Category: Medium Section: 6.5

14. A glass containing 200. g of H2O at 20°C was placed in a refrigerator. The water loses 11.7 kJ as it cools to a constant temperature. What is its new temperature? The specific heat of water is 4.184 J/g·°C.A) 0.013°C B) 4°C C) 6°C D) 14°C E) 34°CAns: C Category: Medium Section: 6.5

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15. A piece of copper with a mass of 218 g has a heat capacity of 83.9 J/°C. What is the specific heat of copper?A) 0.385 J/g·°C D) 1.32 J/g·°CB) 1.83 104 J/g·°C E) 24.5 J/g·°CC) 2.60 J/g·°CAns: A Category: Easy Section: 6.5

16. The specific heat of gold is 0.129 J/g·°C. What is the molar heat capacity of gold?A) 0.039 J/mol·°C D) 39.0 kJ/mol·°CB) 0.129 J/mol·°C E) 197 J/mol·°CC) 25.4 J/mol·°CAns: C Category: Easy Section: 6.5

17. Suppose a 50.0 g block of silver (specific heat = 0.2350 J/g·°C) at 100°C is placed in contact with a 50.0 g block of iron (specific heat = 0.4494 J/g·°C) at 0°C, and the two blocks are insulated from the rest of the universe. The final temperature of the two blocksA) will be higher than 50°C.B) will be lower than 50°C.C) will be exactly 50°C.D) is unrelated to the composition of the blocks.E) cannot be predicted.Ans: B Category: Medium Section: 6.5

18. When 0.7521 g of benzoic acid was burned in a calorimeter containing 1,000. g of water, a temperature rise of 3.60°C was observed. What is the heat capacity of the bomb calorimeter, excluding the water? The heat of combustion of benzoic acid is –26.42 kJ/g.A) 15.87 kJ/°C D) 1.34 kJ/°CB) 4.18 kJ/°C E) 752.1 kJ/°CC) 5.52 kJ/°CAns: D Category: Medium Section: 6.5

19. Naphthalene combustion can be used to calibrate the heat capacity of a bomb calorimeter. The heat of combustion of naphthalene is –40.1 kJ/g. When 0.8210 g of naphthalene was burned in a calorimeter containing 1,000. g of water, a temperature rise of 4.21°C was observed. What is the heat capacity of the bomb calorimeter excluding the water?A) 32.9 kJ/°C B) 7.8 kJ/°C C) 3.64 kJ/°C D) 1.76 kJ/°C E) 15.3 kJ/°CAns: C Category: Medium Section: 6.5

20. Which of the following processes is endothermic?A) O2(g) + 2H2(g) 2H2O(g)B) H2O(g) H2O(l)C) 3O2(g) + 2CH3OH(g) 2CO2(g) + 2H2O(g)D) H2O(s) H2O(l)Ans: D Category: Medium Section: 6.4

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21. A 100. mL sample of 0.200 M aqueous hydrochloric acid is added to 100. mL of 0.200 M aqueous ammonia in a calorimeter whose heat capacity (excluding any water) is 480. J/K. The following reaction occurs when the two solutions are mixed.HCl(aq) + NH3(aq) NH4Cl(aq)The temperature increase is 2.34°C. Calculate H per mole of HCl and NH3 reacted.A) 154 kJ/mol D) –1.96 kJ/molB) 1.96 kJ/mol E) –154 kJ/molC) 485 kJ/molAns: E Category: Difficult Section: 6.5

22. A 0.1326 g sample of magnesium was burned in an oxygen bomb calorimeter. The total heat capacity of the calorimeter plus water was 5,760 J/°C. If the temperature rise of the calorimeter with water was 0.570°C, calculate the enthalpy of combustion of magnesium.Mg(s) + 1/2O2(g) MgO(s)A) –3280 kJ/mol D) 106 kJ/molB) –24.8 kJ/mol E) –602 kJ/molC) 435 kJ/molAns: E Category: Difficult Section: 6.5

23. To which one of the following reactions occurring at 25°C does the symbol H°f[H2SO4(l)] refer?A) 2H(g) + S(g) + 4O(g) H2SO4(l) D) H2SO4(l) 2H(g) + S(s) + 4O(g)B) H2(g) + S(g) + 2O2(g) H2SO4(l) E) H2(g) + S(s) + 2O2(g) H2SO4(l)C) H2SO4(l) H2(g) + S(s) + 2O2(g)Ans: E Category: Medium Section: 6.6

24. To which one of the following reactions occurring at 25°C does the symbol H°f[HNO3(l)] refer?A) H(g) + N(g) + O3(g) HNO3(l)B) (1/2)H2(g) + (1/2)N2(g) + (3/2)O2(g) HNO3(l)C) HNO3(l) (1/2)H2(g) + (1/2)N2(g) + (3/2)O2(g)D) HNO3(l) H(g) + N(g) + 3O(g)E) H2(g) + N2(g) + O3(g) HNO3(l)Ans: B Category: Medium Section: 6.6

25. When 0.560 g of Na(s) reacts with excess F2(g) to form NaF(s), 13.8 kJ of heat is evolved at standard-state conditions. What is the standard enthalpy of formation (H°f) of NaF(s)?A) 24.8 kJ/mol D) –7.8 kJ/molB) 570 kJ/mol E) -570 kJ/molC) –24.8 kJ/molAns: E Category: Medium Section: 6.6

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26. When 18.5 g of HgO(s) is decomposed to form Hg(l) and O2(g), 7.75 kJ of heat is absorbed at standard-state conditions. What is the standard enthalpy of formation (H°f) of HgO(s)?A) –90.7 kJ/mol D) 27.9 kJ/molB) –7.75 kJ/mol E) 143 kJ/molC) 0.419 kJ/molAns: A Category: Medium Section: 6.6

27. Ethanol undergoes combustion in oxygen to produce carbon dioxide gas and liquid water. The standard heat of combustion of ethanol, C2H5OH(l), is –1366.8 kJ/mol. Given that H°f[CO2(g)] = –393.5 kJ/mol and H°f[H2O(l)] = –285.8 kJ/mol, what is the standard enthalpy of formation of ethanol?A) 3,010 kJ/mol D) 687.6 kJ/molB) –687.6 kJ/mol E) 1,367 kJ/molC) –277.6 kJ/molAns: C Category: Difficult Section: 6.6

28. Find the standard enthalpy of formation of ethylene, C2H4(g), given the following data: heat of combustion of C2H4(g) = –1411 kJ/mol; H°f[CO2(g)] = –393.5 kJ/mol; H°f[H2O(l)] = –285.8 kJ/mol.A) 52 kJ/mol D) 1.41 103 kJ/molB) 87 kJ/mol E) 2.77 103 kJ/molC) 731 kJ/molAns: A Category: Difficult Section: 6.6

29. Octane (C8H18) undergoes combustion according to the following thermochemical equation:2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O(l) H°rxn = –11,020 kJ/mol.Given that H°f[CO2(g)] = –393.5 kJ/mol and H°f[H2O(l)] = –285.8 kJ/mol, calculate the standard enthalpy of formation of octane.A) –210 kJ/mol D) –420 kJ/molB) –11,230 kJ/mol E) 420 kJ/molC) 22,040 kJ/molAns: A Category: Medium Section: 6.6

30. Glycine, C2H5O2N, is important for biological energy. The combustion reaction of glycine is given by the equation4C2H5O2N(s) + 9O2(g) 8CO2(g) + 10H2O(l) + 2N2(g) H°rxn = –3857 kJ/molGiven that H°f[CO2(g)] = –393.5 kJ/mol and H°f[H2O(l)] = –285.8 kJ/mol, calculate the enthalpy of formation of glycine.A) –537.2 kJ/mol D) –3,178 kJ/molB) –268.2 kJ/mol E) –964 kJ/molC) 2,149 kJ/molAns: A Category: Medium Section: 6.6

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31. Styrene, C8H8, is one of the substances used in the production of synthetic rubber. When styrene burns in oxygen to form carbon dioxide and liquid water under standard-state conditions at 25°C, 42.62 kJ are released per gram of styrene. Find the standard enthalpy of formation of styrene at 25°C.(Given: H°f[CO2(g)] = –393.5 kJ/mol, H°f[H2O(l)] = –285.8 kJ/mol, H°f[H2O(g)] = –241.8 kJ/mol)A) 323.8 kJ/mol D) ~636.7 kJ/molB) ~4249 kJ/mol E) 147.8 kJ/molC) ~8730 kJ/molAns: E Category: Difficult Section: 6.6

32. Given 2Al(s) + (3/2)O2(g) Al2O3(s), H°f = –1,670 kJ/mol for Al2O3 (s).Determine H° for the reaction 2Al2O3(s) 4Al(s) + 3O2(g).A) 3,340 kJ/mol D) –1,670 kJ/molB) 1,670 kJ/mol E) –835 kJ/molC) –3,340 kJ/molAns: A Category: Easy Section: 6.6

33. Calculate the standard enthalpy of formation of liquid methanol, CH3OH(l), using the following information:C(graph) + O2 CO2(g) H° = –393.5 kJ/molH2(g) + (1/2)O2 H2O(l) H° = –285.8 kJ/molCH3OH(l) + (3/2)O2(g) CO2(g) + 2H2O(l) H° = –726.4 kJ/mol

A) –1,691.5 kJ/mol D) 47.1 kJ/molB) –238.7 kJ/mol E) –47.1 kJ/molC) 1691.5 kJ/molAns: B Category: Difficult Section: 6.6

34. Calculate the standard enthalpy change for the reaction2C8H18(l) + 17O2(g) 16CO(g) + 18H2O(l).Given:2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O(l) H° = –11,020 kJ/mol2CO(g) + O2(g) 2CO2(g) H° = –566.0 kJ/molA) 10,450 kJ/mol D) –6,492 kJ/molB) 6,492 kJ/mol E) –10.450 kJ/molC) 15,550 kJ/molAns: D Category: Medium Section: 6.6

35. During volcanic eruptions, hydrogen sulfide gas is given off and oxidized by air according to the following chemical equation:2H2S(g) + 3O2(g) 2SO2(g) + 2H2O(g)Calculate the standard enthalpy change for the above reaction given:3S(s) + 2H2O(g) 2H2S(g) + SO2(g) H° = 146.9 kJ/molS(s) + O2(g) SO2(g) H° = –296.4 kJ/mol

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A) –1036.1 kJ/mol D) 443.3 kJ/molB) –742.3 kJ/mol E) 742.3 kJ/molC) –149.5 kJ/molAns: A Category: Medium Section: 6.6

36. Calculate the standard enthalpy change for the reaction2C8H18(l) + 21O2(g) 8CO(g) + 8CO2(g) + 18H2O(l).Given:2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O(l) H° = –11,020 kJ/mol2CO(g) + O2(g) 2CO2(g) H° = –566.0 kJ/molA) 1.0454 104 kJ/mol D) –6,492 kJ/molB) –8,756 kJ/mol E) –1.0454 104 kJ/molC) 1.1586 104 kJ/molAns: B Category: Medium Section: 6.6

37. Given the thermochemical equation 2SO2 + O2 2SO3, H°rxn = –198 kJ/mol,what is the standard enthalpy change for the decomposition of one mole of SO3?A) 198 kJ/mol D) 396 kJ/molB) –99 kJ/mol E) –198 kJ/molC) 99 kJ/molAns: C Category: Medium Section: 6.6

38. Given H2(g) + (1/2)O2(g) H2O(l), H° = –286 kJ/mol, determine the standard enthalpy change for the reaction 2H2O(l) 2H2(g) + O2(g).A) H° = –286 kJ/mol D) H° = +572 kJ/molB) H° = +286 kJ/mol E) H° = –143 kJ/molC) H° = –572 kJ/molAns: D Category: Easy Section: 6.6

39. Pentaborane B5H9(s) burns vigorously in O2 to give B2O3(s) and H2O(l). Calculate H°rxn for the combustion of 1 mol of B5H9.H°f[B2O3(s)] = –1,273.5 kJ/molH°f[B5H9(s)] = 73.2 kJ/molH°f[H2O(l)] = –285.8 kJ/molA) –1,2735 kJ/mol D) –9,086 kJ/molB) –4,543 kJ/mol E) –8,448 kJ/molC) –18,170 kJ/molAns: B Category: Difficult Section: 6.6

40. For the reactionC(graphite) + O2(g) CO2(g) H° = –393 kJ/molhow many grams of C(graphite) must be burned to release 275 kJ of heat?A) 22.3 g B) 0.70 g C) 12.0 g D) 17.1 g E) 8.40 gAns: E Category: Medium Section: 6.4

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41. The combustion of butane produces heat according to the equation2C4H10(g) + 13O2(g) 8CO2(g) + 10H2O(l) H°rxn = –5,314 kJ/molWhat is the heat of combustion per gram of butane?A) –32.5 kJ/g D) –2,656 kJ/gB) –45.7 kJ/g E) –15,440 kJ/gC) –91.5 kJ/gAns: B Category: Medium Section: 6.4

42. The combustion of octane produces heat according to the equation2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O(l) H°rxn= –11,020 kJ/molWhat is the heat of combustion per gram of octane?A) –5,510 kJ/g D) –193 kJ/gB) –96.5 kJ/g E) –6.292 105 kJ/gC) –48.2 kJ/gAns: C Category: Medium Section: 6.4

43. The combustion of butane produces heat according to the equation2C4H10(g) + 13O2(g) 8CO2(g) + 10H2O(l) H°rxn= –5,314 kJ/molHow many grams of butane must be burned to release 1.00 104 kJ of heat?A) 30.9 g B) 61.8 g C) 109 g D) 153 g E) 219 gAns: E Category: Medium Section: 6.4

44. The combustion of butane produces heat according to the equation2C4H10(g) + 13O2(g) 8CO2(g) + 10H2O(l) H°rxn= –5,314 kJ/molHow many grams of CO2 are produced per 1.00 104 kJ of heat released?A) 23.4 g B) 44.0 g C) 82.3 g D) 187 g E) 662 gAns: E Category: Medium Section: 6.4

45. Given that CaO(s) + H2O(l) Ca(OH)2(s), H°rxn = –64.8 kJ/mol, how many grams of CaO must react in order to liberate 525 kJ of heat?A) 6.92 g B) 56.1 g C) 455 g D) 606 g E) 3.40 104 gAns: C Category: Medium Section: 6.4

46. The combustion of pentane produces heat according to the equationC5H12(l) + 8O2(g) 5CO2(g) + 6H2O(l) H°rxn= –3,510 kJ/molHow many grams of CO2 are produced per 2.50 103 kJ of heat released?A) 0.0809 g B) 3.56 g C) 31.3 g D) 157 g E) 309 gAns: D Category: Medium Section: 6.4

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47. An average home in Colorado requires 20. GJ of heat per month. How many grams of natural gas (methane) must be burned to supply this energy?CH4(g) + 2O2(g) CO2(g) + 2H2O(l) H°rxn= –890.4 kJ/molA) 1.4 103 g D) 2.2 104 gB) 3.6 105 g E) 1.4 104 gC) 7.1 10–4 gAns: B Category: Medium Section: 6.4

48. Given the thermochemical equation 2SO2(g) + O2(g) 2SO3(g), H°rxn= –198 kJ/mol, how much heat is evolved when 600. g of SO2 is burned?A) 5.46 10–2 kJ D) 59,400 kJB) 928 kJ E) 3.71 103 kJC) 1.85 103 kJAns: B Category: Medium Section: 6.4

49. Determine the heat given off to the surroundings when 9.0 g of aluminum reacts according to the equation 2Al + Fe2O3 Al2O3 + 2Fe, H°rxn= –849 kJ/mol.A) 7.6 103 kJ D) 5.6 102 kJB) 2.8 102 kJ E) 2.5 103 kJC) 1.4 102 kJAns: C Category: Medium Section: 6.4

50. Find the heat absorbed from the surroundings when 15 g of O2 reacts according to the equation O + O2 O3, H°rxn= –103 kJ/mol.A) 4.6 10–3 kJ B) 48 kJ C) 96 kJ D) 32 kJ E) 110 kJAns: B Category: Medium Section: 6.4

51. Ethanol (C2H5OH) burns according to the equationC2H5OH(l) + 3O2(g) 2CO2(g) + 3H2O(l), H°rxn = –1367 kJ/mol.How much heat is released when 35.0 g of ethanol is burned?A) 1,797 kJ B) 1,367 kJ C) 9.61 10–4 kJ D) 4.78 104 kJ E) 1,040 kJAns: E Category: Medium Section: 6.4

52. Methanol (CH3OH) burns according to the equation2CH3OH(l) + 3O2(g) 2CO2(g) + 4H2O(l), H°rxn = –1454 kJ/mol.How much heat, in kilojoules, is given off when 75.0 g of methanol is burned?A) 727 kJ D) 1.70 10–3 kJB) 3.22 103 kJ E) 3.41 103 kJC) 1.45 103 kJAns: D Category: Medium Section: 6.4

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53. Calcium oxide and water react in an exothermic reaction:CaO(s) + H2O(l) Ca(OH)2(s) H°rxn = –64.8 kJ/molHow much heat would be liberated when 7.15 g CaO(s) is dropped into a beaker containing 152g H2O?A) 1.97 10–3 kJ B) 8.26 kJ C) 508 kJ D) 547 kJ E) 555 kJAns: B Category: Medium Section: 6.4

54. Solid sodium peroxide (Na2O2) reacts with liquid water yielding aqueous sodium hydroxide and oxygen gas. How much heat is released when 250.0 L of oxygen gas is produced from the reaction of sodium peroxide and water if the reaction is carried out in an open container at 1.000 atm pressure and 25°C?(Given: H°f[Na2O2(s)] = –510.9 kJ/mol; H°f[NaOH(aq)] = –469.2 kJ/mol; H°f[H2O(l)] = –285.8 kJ/mol)A) 35,400 kJ B) 1740 kJ C) 141.7 kJ D) 3330 kJ E) 2900 kJAns: E Category: Difficult Section: 6.6

55. At 25°C, the standard enthalpy of formation of KCl(s) is –435.87 kJ/mol. When one mole of KCl(s) is formed by reacting potassium vapor and chlorine gas at 25°C, the standard enthalpy of reaction is –525.86 kJ/mol. Find H° for the sublimation of potassium, K(s) K(g), at 25°C.A) –345.88 kJ/mol D) 89.99 kJ/molB) 45.00 kJ/mol E) –525.86 kJ/molC) 345.88 kJ/molAns: D Category: Medium Section: 6.6

56. At 25°C, the standard enthalpy of formation of anhydrous sodium carbonate is –1130.9 kJ/mol, whereas the standard enthalpy of formation of sodium carbonate monohydrate is –1430.1 kJ/mol. Determine H° at 25°C for the reactionNa2CO3(s) + H2O(l) Na2CO3·H2O(s).(Given: H°f[H2O(l)] = –285.8 kJ/mol)A) –13.4 kJ/mol D) –299.2 kJ/molB) –285.8 kJ/mol E) –156.3 kJ/molC) –585.0 kJ/molAns: A Category: Medium Section: 6.6

57. According to the first law of thermodynamics:A) Energy is neither lost nor gained in any energy transformations.B) Perpetual motion is possible.C) Energy is conserved in quality but not in quantity.D) Energy is being created as time passes. We have more energy in the universe now

than when time began.Ans: A Category: Easy Section: 6.3

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58. The heat of solution of KCl is 17.2 kJ/mol and the lattice energy of KCl(s) is 701.2 kJ/mol. Calculate the total heat of hydration of 1 mol of gas phase K+ ions and Cl– ions.A) 718 kJ B) 684 kJ C) –684 kJ D) –718 kJ E) None of these.Ans: C Category: Medium Section: 6.7

59. The heat of solution of LiCl is –37.1 kJ/mol, and the lattice energy of LiCl(s) is 828 kJ/mol. Calculate the total heat of hydration of 1 mol of gas phase Li+ ions and Cl– ions.A) 791 kJ B) 865 kJ C) –865 kJ D) –791 kJ E) None of these.Ans: C Category: Medium Section: 6.7

60. The total heat of hydration of 1 mol of gas phase Li+ ions and Cl – ions is –865 kJ. The lattice energy of LiCl(s) is 828 kJ/mol. Calculate the heat of solution of LiCl.A) 37 kJ/mol D) –37 kJ/molB) 1,693 kJ/mol E) None of these.C) –1,693 kJ/molAns: D Category: Medium Section: 6.7

61. 10.1 g CaO is dropped into a styrofoam coffee cup containing 157 g H2O at 18.0°C.If the following reaction occurs, then what temperature will the water reach, assuming that the cup is a perfect insulator and that the cup absorbs only a negligible amount of heat? (the specific heat of water = 4.18 J/g·°C)CaO(s) + H2O(l) Ca(OH)2(s) H°rxn = –64.8 kJ/molA) 18.02°C B) 35.8°C C) 311°C D) 42.2°C E) 117°CAns: B Category: Medium Section: 6.5

62. The enthalpy change when a strong acid is neutralized by strong base is –56.1 kJ/mol. If 135 mL of 0.450 M HI at 23.15°C is mixed with 145 mL of 0.500 M NaOH, also at 23.15°C, what will the maximum temperature reached by the resulting solution? (Assume that there is no heat loss to the container, that the specific heat of the final solution is 4.18 J/g·°C, and that the density of the final solution is that of water.)A) 26.06°C B) 29.19°C C) 32.35°C D) 20.24°C E) 36.57°CAns: A Category: Difficult Section: 6.5

63. The enthalpy change when a strong acid is neutralized by strong base is –56.1 kJ/mol. If 12.0 mL of 6.00 M HBr at 21.30°C is mixed with 300. mL of 0.250 M NaOH, also at 21.30°C, what will the maximum temperature reached by the resulting solution? (Assume that there is no heat loss to the container, that the specific heat of the final solution is 4.18 J/g·°C, and that the density of the final solution is that of water.)A) 18.20°C B) 24.53°C C) 101.8°C D) 24.40°C E) 34.25°CAns: D Category: Difficult Section: 6.5

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64. Calculate the amount of work done, in joules, when 2.5 mole of H2O vaporizes at 1.0 atm and 25°C. Assume the volume of liquid H2O is negligible compared to that of vapor. (1 L·atm = 101.3 J)A) 6,190 kJ B) 6.19 kJ C) 61.1 J D) 5.66 kJ E) 518 JAns: B Category: Medium Section: 6.3

65. A gas is compressed in a cylinder from a volume of 20.0 L to 2.0 L by a constant pressure of 10.0 atm. Calculate the amount of work done on the system.A) 1.01 104 J B) –180 J C) 1.81 104 J D) –1.81 104 J E) 180 JAns: C Category: Medium Section: 6.3

66. Calculate the amount of work done against an atmospheric pressure of 1.00 atm when 500.0 g of zinc dissolves in excess acid at 30.0°C.Zn(s) + 2H+(aq) Zn2+(aq) + H2(g)A) w = +22.4 kJ D) w = –2.52 kJB) w = +24.9 kJ E) w = –19.3 kJC) w = 0Ans: E Category: Medium Section: 6.3

67. A gas is allowed to expand, at constant temperature, from a volume of 1.0 L to 10.1 L against an external pressure of 0.50 atm. If the gas absorbs 250 J of heat from the surroundings, what are the values of q, w, and E?

Ans: ACategory: Medium Section: 6.3

68. Which of the following processes always results in an increase in the energy of a system?A) The system loses heat and does work on the surroundings.B) The system gains heat and does work on the surroundings.C) The system loses heat and has work done on it by the surroundings.D) The system gains heat and has work done on it by the surroundings.E) None of these is always true.Ans: D Category: Medium Section: 6.3

1


69. For which of these reactions will the difference between H° and E° be the greatest?A) 2H2O2(l) 2H2O(l) + O2(g)B) CaCO3(s) CaO(s) +CO2(g)C) NO(g) + O3(g) NO2(g) + O2(g)D) 2C2H6(g) + 7O2(g) 4CO2(g) + 6H2O(l)E) 4NH3(g) + 5O2(g) 4NO(g) + 6H2O(g)Ans: D Category: Medium Section: 6.4

70. For which of these reactions will the difference between H° and E° be the smallest?A) N2(g) + 3H2(g) 2NH3(g)B) 4PH3(g) P4(g) + 6H2(g)C) H2(g) + Cl2(g) 2HCl(g)D) CO2(g) + 2H2O(l) CH4(g) + 2O2(g)E) P4(s) + 10Cl2(g) 4PCl5(s)Ans: C Category: Medium Section: 6.4

71. At 25°C, the following heats of reaction are known:2ClF(g) + O2(g) Cl2O(g) + F2O(g) H°rxn = 167.4 kJ/mol2ClF3(g) + 2O2(g) Cl2O(g) + 3F2O(g) H°rxn = 341.4 kJ/mol2F2(g) + O2(g) 2F2O(g) H°rxn = –43.4 kJ/molAt the same temperature, use Hess's law to calculate H°rxn for the reaction:ClF(g) + F2(g) ClF3(g)A) –217.5 kJ/mol D) –108.7 kJ/molB) –130.2 kJ/mol E) 465.4 kJ/molC) 217.5 kJ/molAns: D Category: Medium Section: 6.6

72. The bond enthalpy of the Br–Cl bond is equal to H° for the reactionBrCl(g) Br(g) + Cl(g).Use the following data to find the bond enthalpy of the Br–Cl bond.Br2(l) Br2(g) H° = 30.91 kJ/molBr2(g) 2Br(g) H° = 192.9 kJ/molCl2(g) 2Cl(g) H° = 243.4 kJ/molBr2(l) + Cl2(g) 2BrCl(g) H° = 29.2 kJ/mol

A) 219.0 kJ/mol D) 438.0 kJ/molB) 203.5 kJ/mol E) 407.0 kJ/molC) 14.6 kJ/molAns: A Category: Medium Section: 6.6

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73. The heat of solution of ammonium nitrate is 26.2 kJ/mol. If a 5.368 g sample of NH4NO3

is added to 40.0 mL of water in a calorimeter at 23.5°C, what is the minimum temperature reached by the solution? (The specific heat of water = 4.18 J/g·°C; the heat capacity of the calorimeter = 650. J/°C.)A) 14.3°C B) 20.8°C C) –7.7°C D) 25.6°C E) 21.4°CAns: E Category: Difficult Section: 6.5

74. The heat of solution of ammonium chloride is 15.2 kJ/mol. If a 6.134 g sample of NH4Cl is added to 65.0 mL of water in a calorimeter at 24.5°C, what is the minimum temperature reached by the solution? (The specific heat of water = 4.18 J/g·°C; the heat capacity of the calorimeter = 365. J/°C.)A) 27.1°C B) 18.6°C C) 19.7°C D) 21.9°C E) 30.4°CAns: D Category: Difficult Section: 6.5

75. Aluminum oxide can be reduced to aluminum metal using carbon, the other reaction product being carbon monoxide. Determine the enthalpy change when 12.5 g of aluminum is produced by this method. [H°f(carbon monoxide) = –110.5 kJ/mol; H°f(aluminum oxide) = –1669.8 kJ/mol]A) 725 kJ B) 697 kJ C) 310 kJ D) 361 kJ E) 1504 kJAns: C Category: Difficult Section: 6.6

76. Ozone (O3) in the atmosphere can be converted to oxygen gas by reaction with nitric oxide (NO). Nitrogen dioxide is also produced in the reaction. What is the enthalpy change when 8.50L of ozone at a pressure of 1.00 atm and 25°C reacts with 12.00 L of nitric oxide at the same initial pressure and temperature? [H°f(NO) = 90.4 kJ/mol; H°f(NO2) = 33.85 kJ/mol; H°f(O3) = 142.2 kJ/mol]A) –69.2 kJ B) –19.7 kJ C) –1690 kJ D) –97.6 kJ E) –167 kJAns: A Category: Difficult Section: 6.6

77. Define specific heat.Ans: The amount of heat required to raise the temperature of one gram of a substance by

one degree Celsius.Category: Easy Section: 6.5

78. How many grams of ethylene (C2H4) would have to be burned to produce 450 kJ of heat?C2H4(g) + 3O2(g) 2CO2(g) + H2O(l) H°rxn = –1411 kJ/molAns: 8.95 gCategory: Medium Section: 6.4

79. Calculate the enthalpy of reaction for H2(g) + C2H4(g) C2H6(g).[H°f(C2H4(g)) = 52.3 kJ/mol; H°f(C2H6(g)) = –84.7 kJ/mol]Ans: –137 kJ/molCategory: Medium Section: 6.6

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80. The enthalpy of combustion of acetylene C2H2 is described byC2H2(g) + (5/2)O2(g) 2CO2(g) + H2O(l) H°rxn= –1299 kJ/molCalculate the enthalpy of formation of acetylene, given the following enthalpies of formationH°f[CO2(g)] = –393.5 kJ/molH°f[H2O(l)] = –285.8 kJ/molAns: 226 kJ/molCategory: Medium Section: 6.6

81. Given the following H° values,H2(g) + O2(g) H2O(l) H°f = –285.8 kJ/molH2O2(l) H2(g) + O2(g) H°rxn = 187.6 kJ/molcalculate H°rxn for the reaction H2O2(l) H2O(l) + O2(g),Ans: –98.2 kJ/molCategory: Medium Section: 6.6

82. The heat of solution of calcium chloride CaCl2 is –82.8 kJ/mol, and the combined heats of hydration of 1 mole of gaseous calcium ions and 2 mole of gaseous chloride ions is –2327 kJ. What is the lattice energy of calcium chloride?Ans: 2,244 kJ/molCategory: Medium Section: 6.7

83. The heat of solution of NH4NO3 is 26.2 kJ/mol. Is heat evolved or absorbed when a solution of NH4NO3 is diluted by addition of more water?Ans: AbsorbedCategory: Easy Section: 6.7

84. A 26.2 g piece of copper metal is heated from 21.5°C to 201.6°C. Calculate the amount of heat absorbed by the metal. The specific heat of Cu is 0.385 J/g·°C.Ans: 1,820 JCategory: Medium Section: 6.5

85. A 0.1946 g piece of magnesium metal is burned in a constant-volume calorimeter that has a heat capacity of 1349 J/°C. The calorimeter contains 500. g of water and the temperature rise is 1.40°C. Calculate the heat of combustion of magnesium metal in kJ/g, given that the specific heat of water = 4.184 J/g·°C.Ans: 24.8 kJ/gCategory: Medium Section: 6.5

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86. A 0.3423 g sample of pentane, C5H12, was burned in a bomb calorimeter. The temperature of the calorimeter and the 1.000 kg of water contained therein rose from 20.22°C to 22.82°C. The heat capacity of the calorimeter is 2.21 kJ/°C. The heat capacity of water = 4.184 J/g·°C. How much heat was given off during combustion of the sample of pentane?Ans: 16.6 kJCategory: Medium Section: 6.5

87. A 0.3423 g sample of pentane, C5H12, was burned in a bomb calorimeter. The temperature of the calorimeter and the 1.000 kg of water contained therein rose from 20.22°C to 22.82°C. The heat capacity of the calorimeter is 2.21 kJ/°C. The heat capacity of water = 4.184 J/g·°C. What is the heat of combustion, in kilojoules, per gram of pentane?Ans: 48.6 kJ/gCategory: Medium Section: 6.5

88. A 0.3423 g sample of pentane, C5H12, was burned in a bomb calorimeter. The temperature of the calorimeter and the 1.000 kg of water contained therein rose from 20.22°C to 22.82°C. The heat capacity of the calorimeter is 2.21 kJ/°C. The heat capacity of water = 4.184 J/g·°C. What is the heat of combustion, in megajoules (MJ), per mole of pentane?Ans: 3.50 MJ/molCategory: Medium Section: 6.5

89. The heat of combustion of propane, C3H8, 2220 kJ/mol. The specific heat of copper is 0.385 J/g°C. How many grams of propane must be burned to raise the temperature of a 10.0 kg block of copper from 25.0°C to 65.0°C, assuming none of the heat is lost to the surroundingsAns: 3.06 gCategory: Medium Section: 6.5

90. The residential rate for natural gas is about $15 per thousand cubic foot. Burning one cubic foot of natural gas releases about 1080 kJ of heat. How much would it cost to heat the water in a 25,000 gallon swimming pool from 52°F to 78°F, assuming all of the heat from burning the natural gas went towards warming the water? (1 gal = 3.785 L; the specific heat of water = 4.184 J/g·°C)Ans: $79Category: Difficult Section: 6.5

91. The heat of neutralization of HCl by NaOH is H°rxn = –56.2 kJ/mol. How much heat is released when 125 mL of 1.750 M HCl is mixed with 195 mL of 0.667 M NaOH?Ans: 7.31 kJCategory: Difficult Section: 6.5

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92. The heat released when one mole of water is formed from the elements is 1,198 kJ. An experiment was conducted that permitted water to form in this manner, and the heat was contained in 2.0 liters of water. The water temperature before the reaction was 34.5°C, and after the reaction it had risen to 52.0°C. How many moles of water were formed? (The specific heat of water is 4.184 J/g·°C.)Ans: 0.12 moleCategory: Medium Section: 6.5

93. When an automobile engine starts, the metal parts immediately begin to absorb heat released during the combustion of gasoline. How much heat will be absorbed by a 165 kg iron engine block as the temperature rises from 15.7°C to 95.7°C? (The specific heat of iron is 0.489 J/g·°C.)Ans: 6,450 kJCategory: Medium Section: 6.5

94. The value of H°rxn for the following reaction is –6535 kJ/mol.2C6H6(l) + 15O2(g) 12CO2(g) + 6H2O(g)How many kilojoules of heat will be evolved during the combustion of 16.0 g of C6H6(l)?Ans: 669 kJCategory: Medium Section: 6.4

95. What would be the standard enthalpy change for the reaction of one mole of H2(g) with one mole of Cl2(g) to produce two moles of HCl(g) at standard state conditions?[H°f (HCl(g))= –92.3 kJ/mol]Ans: –185 kJCategory: Medium Section: 6.6

96. What is the standard enthalpy of formation of H2(g) at 25°C?Ans: 0 kJ/molCategory: Easy Section: 6.6

97. Find H°rxn for the reactionCH4(g) + 2O2(g) CO2(g) + 2H2O(l).[H°f (CH4(g)) = –74.8 kJ/mol; H°f (CO2(g)) = –393.5 kJ/mol; H°f (H2O(l)) = –285.5 kJ/mol]Ans: -889.7 kJ/molCategory: Medium Section: 6.6

98. Find H°rxn for the reaction2Ag2S(s) + 2H2O(l) 4Ag(s) + 2H2S(g) + O2(g).[H°f (Ag2S(s)) = –32.6 kJ/mol; H°f (H2S(g)) = –20.5 kJ/mol; H°f (H2O(l)) = –285.5 kJ/mol]Ans: 595.2 kJ/molCategory: Medium Section: 6.6

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99. Find H°rxn for the reaction2Na(s) + 2H2O(l) 2NaOH(aq) + 2H2(g).[H°f (NaOH(aq)) = –426.8 kJ/mol; H°f (H2O(l)) = –285.5 kJ/mol]Ans: –282.6 kJCategory: Medium Section: 6.6

100. The specific heat of silver is 0.235 J/g·°C. How many joules of heat are required to heat a 75 g silver spoon from 20°C to 35°C?Ans: 260 JCategory: Easy Section: 6.5

101. At body temperature 2,404 joules of energy are required to evaporate 1.00 g of water. After vigorous exercise, a person feels chilly because the body is giving up heat to evaporate the perspiration. A typical person perspires 25 mL of water after 20. minutes of exercise. How much body heat is this person using to evaporate this water?Ans: 6.0 104 JCategory: Easy Section: 6.4

102. The combustion of one mole of benzene, C6H6, in oxygen liberates 3268 kJ of heat. The products of the reaction are carbon dioxide and water. How much heat is given off when 183 g of oxygen are reacted with excess benzene?Ans: 2490 kJCategory: Difficult Section: 6.4

103. A feverish student weighing 75 kilograms was immersed in 400. kg of water at 4.0°C to try to reduce the fever. The student's body temperature dropped from 40.0°C to 37.0°C. Assuming the specific heat of the student to be 3.77 J/g·°C, what was the final temperature of the water?Ans: 4.5°CCategory: Difficult Section: 6.5

104. The specific heats of water and iron are 4.184 and 0.444 J/g°C, respectively. When equal masses of water and iron both absorb the same amount of heat, the temperature increase of the water will be 5.42 times greater than that of the iron.Ans: True Category: Medium Section: 6.5

105. Chemical reactions in a bomb calorimeter occur at constant pressure.Ans: True Category: Easy Section: 6.5

106. If 2Mg(s) + O2(g) 2MgO(s), H° = –1203.6 kJ/mol.For Mg(s) + (1/2)O2(g) MgO(s), the enthalpy change is H = –601.8 kJ/mol.Ans: True Category: Easy Section: 6.6

107. The heat capacity of 20.0 g of water is 83.7 J/°C.Ans: True Category: Medium Section: 6.5

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108. The work done on the surroundings by the expansion of a gas is w = –PV.Ans: True Category: Easy Section: 6.3

109. The heat absorbed by a system at constant pressure is equal to E + PV.Ans: True Category: Easy Section: 6.4

110. In an endothermic process, heat is absorbed by the system.Ans: True Category: Easy Section: 6.2

111. A home aquarium is an example of an open system.Ans: True Category: Easy Section: 6.2

112. The heat of hydration (Hhydr) of ions is always endothermic.Ans: False Category: Medium Section: 6.7

1. In the following diagram of a wave

A) (a) is amplitude and (b) is wavelength D) (a) is amplitude and (b) is frequency

B) (a) is frequency and (b) is amplitude E) (a) is wavelength and (b) is amplitude

C) (a) is wavelength and (b) is frequency

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Ans: E Category: Easy Section: 7.1

2. As the frequency of an electromagnetic wave increasesA) its speed must increase. C) its amplitude must increase.B) its wavelength must increase. D) its energy must increase.

Ans: D Category: Easy Section: 7.2

3. What is the wavelength of radiation that has a frequency of 5.39 1014 s–1? (c = 2.9979 108 m/s)

A) 1.80 10–3 nm B) 556 nm C) 618 nm D) 6180 nm E) 1.61 1023 nm

Ans: B Category: Easy Section: 7.1

4. What is the wavelength of radiation that has a frequency of 2.10 1014 s –1?A) 6.30 1022 m D) 1.43 10–6 mB) 7.00 102 nm E) 3.00 108 mC) 7.00 105 m


5. Calculate the frequency of visible light having a wavelength of 486 nm.A) 2.06 1014 /s D) 1.20 10–15 /sB) 2.06 106 /s E) 4.86 10–7 /sC) 6.17 1014 /s

Ans: C Category: Easy Section: 7.1

6. Calculate the frequency of visible light having a wavelength of 686 nm.A) 4.37 1014 /s D) 2.29 10–15 /sB) 4.37 105 /s E) 2.29 10–6 /sC) 6.17 1014 /s

Ans: A Category: Easy Section: 7.1

7. What is the energy in joules of one photon of microwave radiation with a wavelength 0.122 m? (c = 2.9979 108 m/s; h = 6.626 10–34 Js)

A) 2.70 10–43 J D) 4.07 10–10 JB) 5.43 10–33 J E) 2.46 109 JC) 1.63 10–24 J

Ans: C Category: Medium Section: 7.2

8. What is the energy in joules of a mole of photons associated with visible light of wavelength 486 nm?

A) 6.46 10–16 J D) 12.4 kJB) 6.46 10–25 J E) 246 kJC) 2.46 10–4 J

Ans: E Category: Medium Section: 7.2

9. What is the energy in joules of a mole of photons associated with red light of

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wavelength 7.00 102 nm?A) 256 kJ B) 1.71 105 J C) 4.72 10–43 J D) 12.4 kJ E) 2.12 1042 JAns: B Category: Medium Section: 7.2

10. What is the binding energy (in J/mol or kJ/mol) of an electron in a metal whose threshold frequency for photoelectrons is 2.50 1014 /s?

A) 99.7 kJ/mol D) 7.22 1017 kJ/molB) 1.66 10–19 J/mol E) 1.20 10–6 J/molC) 2.75 10–43 J/mol

Ans: A Category: Medium Section: 7.2

11. Complete this sentence: Atoms emit visible and ultraviolet lightA) as electrons jump from lower energy levels to higher levels.B) as the atoms condense from a gas to a liquid.C) as electrons jump from higher energy levels to lower levels.D) as they are heated and the solid melts to form a liquid.E) as the electrons move about the atom within an orbit.


12. Calculate the energy, in joules, required to excite a hydrogen atom by causing an electronic transition from the n = 1 to the n = 4 principal energy level. Recall that the energy levels of the H atom are given by

En = –2.18 10–18 J(1/n2)A) 2.07 10–29 J D) 3.27 10–17 JB) 2.19 105 J E) 2.25 10–18 JC) 2.04 10–18 J


13. Calculate the wavelength, in nanometers, of the light emitted by a hydrogen atom when its electron falls from the n = 7 to the n = 4 principal energy level. Recall that the energy levels of the H atom are given by

En = –2.18 10–18 J(1/n2)A) 4.45 10–20 nm D) 1.38 1014 nmB) 2.16 10–6 nm E) 2.16 103 nmC) 9.18 10–20 nm


14. Calculate the frequency of the light emitted by a hydrogen atom during a transition of its electron from the n = 6 to the n = 3 principal energy level. Recall that for hydrogen En = –2.18 10–18 J(1/n2).

A) 1.64 1015 /s D) 1.82 10–19 /sB) 9.13 1013 /s E) 2.74 1014/sC) 3.65 1014 /s


15. Calculate the frequency of the light emitted by a hydrogen atom during a

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transition of its electron from the n = 4 to the n = 1 principal energy level. Recall that for hydrogen En = –2.18 10 –18 J(1/n2)

A) 3.08 1015 /s D) 1.35 10–51 /sB) 1.03 108 /s E) 8.22 1014 /sC) 2.06 1014 /s


16. Calculate the wavelength of the light emitted by a hydrogen atom during a transition of its electron from the n = 4 to the n = 1 principal energy level. Recall that for hydrogen En = –2.18 10–18 J(1/n2)

A) 97.2 nm B) 82.6 nm C) 365 nm D) 0.612 nm E) 6.8 10–18 nmAns: A Category: Medium Section: 7.3

17. The second line of the Balmer series occurs at a wavelength of 486.1 nm. What is the energy difference between the initial and final levels of the hydrogen atom in this emission process?

A) 2.44 1018 J D) 4.09 10–28 JB) 4.09 10–19 J E) 1.07 10–48 JC) 4.09 10–22 J

Ans: B Category: Medium Section: 7.3

18. A proton is roughly 1800 times more massive than an electron. If a proton and an electron are traveling at the same speed,

A) the wavelength of the photon will be about 1800 times longer than the wavelength of the electron.

B) the wavelength of the photon will be about times longer than the wavelength of the electron.

C) the wavelength of the photon will be roughly equal to the wavelength of the electron.

D) the wavelength of the electron will be about times longer than the wavelength of the photon.

E) the wavelength of the electron will be about 1800 times longer than the wavelength of the photon.


19. A photon is roughly 1800 times more massive than an electron. If a proton and an electron have the same kinetic energy,

A) the wavelength of the photon will be about 1800 times longer than the wavelength of the electron.

B) the wavelength of the photon will be about times longer than the wavelength of the electron.

C) the wavelength of the photon will be roughly equal to the wavelength of the electron.

D) the wavelength of the electron will be about times longer than the

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wavelength of the photon.E) the wavelength of the electron will be about 1800 times longer than the

wavelength of the photon.Ans: D Category: Difficult Section: 7.3

20. If a hydrogen atom and a helium atom are traveling at the same speed,A) the wavelength of the hydrogen atom will be about 4 times longer than the

wavelength of the helium atom.B) the wavelength of the hydrogen atom will be about 2 times longer than the

wavelength of the helium.C) the wavelength of the hydrogen atom will be roughly equal to the wavelength of

the helium atom.D) the wavelength of the helium atom will be about 2 times longer than the

wavelength of the hydrogen atom.E) the wavelength of the helium atom will be about 4 times longer than the

wavelength of the hydrogen atom.Ans: A Category: Medium Section: 7.3

21. If a hydrogen atom and a helium atom have the same kinetic energy,A) the wavelength of the hydrogen atom will be about 4 times longer than the

wavelength of the helium atom.B) the wavelength of the hydrogen atom will be about 2 times longer than the

wavelength of the helium.C) the wavelength of the hydrogen atom will be roughly equal to the wavelength of

the helium atom.D) the wavelength of the helium atom will be about 2 times longer than the

wavelength of the hydrogen atom.E) the wavelength of the helium atom will be about 4 times longer than the

wavelength of the hydrogen atom.Ans: B Category: Difficult Section: 7.3

22. In an electron microscope, electrons are accelerated to great velocities. Calculate the wavelength of an electron traveling with a velocity of 7.0 103 kilometers per second. The mass of an electron is 9.1 10–28 g.

A) 1.0 10–13 m B) 1.0 10–7 m C) 1.0 m D) 1.0 10–10 mAns: D Category: Medium Section: 7.4

23. Calculate the wavelength associated with a 20Ne+ ion moving at a velocity of 2.0 105 m/s. The atomic mass of Ne-20 is 19.992 amu.

A) 1.0 10–13 m D) 9.7 1012 mB) 1.0 10–16 m E) 2.0 10–13 cmC) 1.0 10–18 m


24. Calculate the wavelength of a neutron that has a velocity of 250 cm/s. (The mass of a neutron = 1.675 10–24 g; h = 6.626 10–34 Js)

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A) 16 pm B) 0.016 nm C) 0.16 nm D) 160 nm E) 1.6 10–4 mAns: D Category: Medium Section: 7.4

25. A common way of initiating certain chemical reactions with light involves the generation of free halogen atoms in solution. If H for the reaction Cl2(g) 2Cl(g) is 242.8 kJ/mol, what is the longest wavelength of light that will produce free chlorine atoms in solution?

A) 246.3 nm B) 465.2 nm C) 349.3 nm D) 698.6 nm E) 492.6 nmAns: E Category: Difficult Section: 7.2

26. The longest wavelength of light that causes electrons to be ejected from the surface of a copper plate is 243 nm. What is the maximum velocity of the electrons ejected when light of wavelength 200. nm shines on a copper plate?

A) 1.48 106 m/s D) 1.97 104 m/sB) 6.22 105 m/s E) 1.34 106 m/sC) 4.67 104 m/s

Ans: B Category: Difficult Section: 7.2

27. When photons with a wavelength of 310. nm strike a magnesium plate, the maximum velocity of the ejected electrons is 3.45 105 m/s. Calculate the binding energy of electrons to the magnesium surface.

A) 386 kJ/mol D) 321 kJ/molB) 419 kJ/mol E) 353 kJ/molC) 32.7 kJ/mol

Ans: E Category: Difficult Section: 7.2

28. Electrons can be used to probe the arrangement of atoms on a solid surface if the wavelength of the electrons is comparable with the spacing between the atoms. Which of the following electron velocities would be appropriate for use in this application if the atoms are separated by 0.320 nm?

A) 2.27 106 m/s D) 4.41 106 m/sB) 1.24 103 m/s E) 8.06 103 m/sC) 3.00 108 m/s

Ans: A Category: Difficult Section: 7.4

29. A single pulse of a laser yields an average of 5.00 1018 photons with = 633 nm. If melting ice to water at 0°C requires 6.01 kJ/mol, what is the fewest number of laser pulses need to melt 10.0 g of ice?

A) 3830 B) 3340 C) 38300 D) 2120 E) 212Ans: D Category: Difficult Section: 7.2

30. Which one of the following sets of quantum numbers is not possible?

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Ans: BCategory: Medium Section: 7.6

31. Which one of the following sets of quantum numbers is not possible?

Ans: BCategory: Medium Section: 7.6

32. What is the maximum number of electrons in an atom that can have the following set of quantum numbers?

n = 4 l = 3 ml = –2 ms = +1/2A) 0 B) 1 C) 2 D) 6 E) 10Ans: B Category: Easy Section: 7.8

33. A possible set of quantum numbers for the last electron added to complete an atom of gallium (Ga) in its ground state is

Ans: CCategory: Medium Section: 7.8

34. A possible set of quantum numbers for the last electron added to complete an atom of germanium (Ge) in its ground state is

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Ans: CCategory: Medium Section: 7.8

35. Electrons in an orbital with l = 3 are in a/anA) d orbital. B) f orbital. C) g orbital. D) p orbital. E) s orbital.Ans: B Category: Easy Section: 7.6

36. The number of orbitals in a d subshell isA) 1 B) 2 C) 3 D) 5 E) 7Ans: D Category: Easy Section: 7.6

37. The maximum number of electrons that can occupy an energy level described by the principal quantum number, n, is

A) n B) n + 1 C) 2n D) 2n2 E) n2

Ans: D Category: Medium Section: 7.8

38. How many orbitals are allowed in a subshell if the angular momentum quantum number for electrons in that subshell is 3?

A) 1 B) 3 C) 5 D) 7 E) 9Ans: D Category: Medium Section: 7.6

39. "No two electrons in an atom can have the same four quantum numbers" is a statement of

A) the Pauli exclusion principle. D) de Broglie's relation.B) Bohr's equation. E) Dalton's atomic theory.C) Hund's rule.

Ans: A Category: Easy Section: 7.8

40. The orbital diagram for a ground-state nitrogen atom is

Ans: ACategory: Medium Section: 7.8

41. The orbital diagram for a ground-state oxygen atom is

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Ans: DCategory: Medium Section: 7.8

42. The orbital diagram for a ground state carbon atom is

Ans: DCategory: Medium Section: 7.8

43. Which ground-state atom has an electron configuration described by the following orbital diagram?

A) phosphorus B) germanium C) selenium D) tellurium E) none of these



A) antimony B) germanium C) indium D) lead E) tinAns: E Category: Medium Section: 7.9


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A) phosphorus B) nitrogen C) arsenic D) vanadium E) none of theseAns: A Category: Medium Section: 7.9

46. How many unpaired electrons does a ground-state atom of sulfur have?A) 0 B) 1 C) 2 D) 3 E) 4Ans: C Category: Medium Section: 7.9

47. A ground-state atom of arsenic hasA) no unpaired electrons. D) three unpaired electrons.B) one unpaired electron.E) four unpaired electrons.C) two unpaired electrons.


48. Which element has the following ground-state electron configuration?1s22s22p63s2

A) Na B) Mg C) Al D) Si E) NeAns: B Category: Medium Section: 7.9

49. Which element has the following ground-state electron configuration?[Kr]5s24d105p3

A) Sn B) Sb C) Pb D) Bi E) TeAns: B Category: Medium Section: 7.9

50. Which element has the following ground-state electron configuration?[Ar]4s23d104p5

A) aresnic B) bromine C) iodine D) selenium E) telleriumAns: B Category: Medium Section: 7.9

51. Which element has the following ground-state electron configuration?[Kr]5s14d5

A) Mn B) Mo C) Nb D) Re E) TcAns: B Category: Medium Section: 7.9

52. Which element has the following ground-state electron configuration?[Kr]5s24d105p2

A) Sn B) Sb C) Pb D) Ge E) TeAns: A Category: Medium Section: 7.9

53. The electron configuration of a ground-state Co atom isA) [Ar]4s23d7 D) [Ar]4s13d5

B) 1s22s22p63s23d9 E) [Ar]4s24d7

C) [Ne]3s23d7


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54. The electron configuration of a ground-state vanadium atom isA) [Ar]4s24d3 B) [Ar]4s24p3 C) [Ar]4s23d3 D) [Ar]3d5


55. The electron configuration of a ground-state copper atom isA) [Ar]4s24d4 B) [Ar]4s24p63d3 C) [Ar]4s23d9 D) [Ar]3d9 E) [Ar]4s13d10


56. The ground-state electron configuration for an atom of indium isA) [Kr]5s24p64d5 D) [Kr]5s25p64d5

B) [Ar]4s23d104p1 E) [Kr]5s24d105p1

C) [Ar]4s24p63d5


57. Which of the following is the ground-state electron configuration of a calcium atom?

A) [Ne]3s2 B) [Ne]3s23p6 C) [Ar]4s13d1 D) [Ar]4s2 E) [Ar]3d2


58. How many electrons are there in the 2nd principal energy level (n = 2) of a phosphorus atom?

A) 3 B) 5 C) 6 D) 8 E) 10Ans: D Category: Medium Section: 7.9

59. How many electrons are there in the 3rd principal energy level (n = 3) of a phosphorus atom?

A) 3 B) 5. C) 6 D) 8 E) 10Ans: B Category: Medium Section: 7.9

60. A ground-state atom of manganese has ___ unpaired electrons and is _____.A) 0, diamagneticD) 5, paramagneticB) 2, diamagneticE) 7, paramagneticC) 3, paramagnetic


61. A ground-state atom of vanadium has ___ unpaired electrons and is _____.A) 0, diamagneticD) 5, paramagneticB) 2, diamagneticE) 4, diamagneticC) 3, paramagnetic


62. A ground-state atom of iron has ___ unpaired electrons and is _____.A) 0, diamagneticD) 5, paramagneticB) 6, diamagneticE) 4, paramagneticC) 3, paramagnetic


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63. Transition metal elements have atoms or ions with partially filledA) s subshells. D) f subshells.B) p subshells. E) g subshells.C) d subshells.


64. Lanthanide (or rare earth elements) have atoms or ions with partially filledA) s subshells. D) f subshells.B) p subshells. E) g subshells.C) d subshells.


65. Which choice lists two elements with ground-state electron configurations that are well known exceptions to the Aufbau principle?

A) Cu and C B) Cr and Cu C) Cs and Cl D) Rb and Co E) Fe and CoAns: B Category: Medium Section: 7.9

66. A ground-state chromium atom has how many unpaired electrons?A) 1 B) 2 C) 4 D) 5 E) 6Ans: E Category: Medium Section: 7.9

67. Which of the following is the electron configuration of an excited state of an oxygen atom?

A) 1s22s22p4 B) 1s22s22p5 C) 1s22s22p33s1 D) 1s22s22p6 E) 1s22s22p3


68. Which of the following is the electron configuration of an excited state of an iron atom?

A) [Ar]4s23d7 B) [Ar]4s23d6 C) [Ar]4s23d8 D) [Ar]4s13d7 E) [Ar]4s13d5


69. Which of the following is the electron configuration of an excited state of a copper atom?

A) [Ar]4s23d9 D) [Ar]4s23d8

B) [Ar]4s13d10 E) [Ar]4s03d10

C) [Ar]4s13d8


70. The ground-state electron configuration of Cr, Mo, and Ag are exceptions to the Aufbau principle. Which of the following is the electron configuration for Mo?

A) [Kr]5s14d5 B) [Kr]5s24d4 C) [Xe]6s25d4 D) [Ar]4s24d4 E) [Kr]5s24d6


71. How many electrons in a ground-state tellurium atom are in orbitals labeled by l = 1?

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A) 4 B) 10 C) 12 D) 16 E) 22Ans: E Category: Medium Section: 7.9

72. How many electrons in a ground-state cadmium atom are in orbitals labeled by ml

= –1?A) 2 B) 10 C) 12 D) 18 E) 36Ans: B Category: Medium Section: 7.9

73. Which of the following ground-state atoms is diamagnetic?A) Ca B) As C) Cu D) Fe E) none of theseAns: A Category: Medium Section: 7.9

74. Which of the following atoms is paramagnetic both in its ground state and in all of its excited states?

A) C B) N C) O D) Ti E) CrAns: B Category: Difficult Section: 7.9

75. Which of the following is diamagnetic both in its ground state and in all of its excited states?

A) Mg B) Ne C) Cu D) Zn E) none of theseAns: E Category: Difficult Section: 7.9

76. The electron in a hydrogen atom falls from an excited energy level to the ground state in two steps, causing the emission of photons with wavelengths of 2624 and 97.2 nm. What is the quantum number of the initial excited energy level from which the electron falls?

A) 2 B) 3 C) 4 D) 6 E) 8Ans: D Category: Difficult Section: 7.3

77. The electron in a hydrogen atom falls from an excited energy level to the ground state in two steps, causing the emission of photons with wavelengths of 1870 and 102.5 nm. What is the quantum number of the initial excited energy level from which the electron falls?

A) 2 B) 3 C) 4 D) 6 E) 8Ans: C Category: Difficult Section: 7.3

78. When the electron in a hydrogen atom falls from the n = 3 excited energy level to the ground state energy level, a photon with wavelength is emitted. An electron having this same wavelength would have a velocity of

A) 7.10 103 m/s D) 7.10 m/sB) 2.93 106 m/s E) 3.00 108 m/sC) 2.93 103 m/s


79. When the electron in a hydrogen atom falls from its first excited energy level to the ground state energy level, a photon with wavelength is emitted. A proton having this same wavelength would have a velocity of

A) 3.87 m/s B) 5990 m/s C) 1.21 10–7 m/s D) 3.26 m/s E) 5.99 m/s

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80. Breaking the oxygen-oxygen bond in hydrogen peroxide requires 210 kJ/mol. What is the longest wavelength of light that can cause this bond to be broken?

A) 5.7 10–4 m D) 9.5 10–28 mB) 9.5 10–31 m E) 5.7 10–7 mC) 2.8 10–7 m


81. Rank the following types of electromagnetic radiation from lowest energy to highest energy: infrared, microwave, radio waves, gamma rays, visible, and ultraviolet.

Ans: radio waves < microwaves < infrared < visible < ultraviolet < gamma raysCategory: Medium Section: 7.1

82. An FM radio station broadcasts at a frequency of 101.7 MHz. Calculate the wavelength of the broadcast signal in meters. (c = 2.9979 108 m/s)

Ans: 2.948 mCategory: Easy Section: 7.1

83. An AM radio station broadcasts at a frequency of 1270 kHz. Calculate the wavelength of the broadcast signal in meters. (c = 2.9979 108 m/s)

Ans: 236 mCategory: Medium Section: 7.1

84. Write the ground state electron configuration for the selenium atom.Ans: [Ar] 4s23d104p4

Category: Medium Section: 7.9

85. Write the ground state electron configuration for the phosphorus atom.Ans: [Ne] 3s23p3


86. Write the ground state electron configuration for an iodine atom.Ans: [Kr] 5s24d105p5


87. Write the ground state electron configuration for a lead atom.Ans: [Xe] 6s24f145d106p2


88. Write the ground state electron configuration for Ni.Ans: [Ar] 4s23d8


89. Write the ground state electron configuration for Cr.Ans: [Ar] 4s13d5

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90. Calculate the energy of a photon of light with a wavelength of 360 nm.Ans: 5.5 10 –19 J


91. What is the difference in the electron configuration between carbon–14 and carbon–12?

Ans: There is no differenceCategory: Easy Section: 7.8

92. With regard to electron behavior, what happens when light is absorbed or emitted by an atom?

Ans: The electrons move between orbitals.Category: Easy Section: 7.3

93. What is the total number of electrons possible in the 2p orbitals?Ans: 6

Category: Easy Section: 7.8

94. What is the total number of electrons possible in the 6s orbital?Ans: 2

Category: Easy Section: 7.8

95. What is the ground-state electron configuration for chlorine?Ans: 1s22s22p63s23p5 or [Ne]3s23p5


96. If one electron is added to the outer shell of chlorine, it would have the same electron configuration as what element?

Ans: argonCategory: Easy Section: 7.9

97. What is the electron configuration of calcium?Ans: 1s22s22p63s23p64s2 or [Ar]4s2


98. If we take away two electrons from the outer shell of calcium, it would have the same electron configuration as what element?

Ans: argonCategory: Easy Section: 7.9

99. The colors of the visible spectrum are blue, green, orange, red, violet, and yellow. Of these colors, _______ has the most energy.

Ans: violetCategory: Easy Section: 7.1

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100. The colors of the visible spectrum are blue, green, orange, red, violet, and yellow. Of these colors, ______ has the least energy.

Ans: redCategory: Easy Section: 7.1

101. The colors of the visible spectrum are blue, green, orange, red, violet, and yellow. Of these colors, _______ has the longest wavelength.

Ans: redCategory: Easy Section: 7.1

102. The colors of the visible spectrum are blue, green, orange, red, violet, and yellow. Of these colors, ______ has the shortest wavelength.

Ans: violetCategory: Easy Section: 7.1

103. What is the wavelength, in meters, of an alpha particle with a kinetic energy of 8.0 10–13 J. (mass of an alpha particle = 4.00150 amu; 1 amu = 1.67 10–27 kg)

Ans: 6.4 10–15 mCategory: Medium Section: 7.4

104. What is the wavelength, in meters, of an alpha particle with a kinetic energy of 8.0 10–13 J. [mass of an alpha particle = 4.00150 amu; 1 amu = 1.67 10–27 kg]

Ans: 6.4 10–15 mCategory: Medium Section: 7.4

105. The scattering of helium atoms by a solid can be used to gain information about the lattice of atoms, provided the wavelength of the helium atoms is comparable to the dimensions of the lattice. What is the wavelength, in picometers, of a helium-4 atom with a kinetic energy of 0.10 eV. (mass of 4He = 4.0026 amu; 1 amu = 1.67 10–24 g; 1 eV = 1.602 10–19 J; h = 6.626 10–34 Js)

Ans: 45 pmCategory: Difficult Section: 7.4

106. What is the wavelength of a ball bearing with a mass of 10.0 g, and a velocity of 10.0 cm/s?

Ans: 6.63 10–22 nmCategory: Medium Section: 7.4

107. The bonds of oxygen molecules are broken by sunlight. The minimum energy required to break the oxygen-oxygen bond is 495 kJ/mol. What is the wavelength of sunlight that can cause this bond breakage?

Ans: 242 nmCategory: Medium Section: 7.2

108. A photovoltaic cell converts light into electrical energy. Suppose a certain

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photovoltaic cell is only 63.5% efficient, in other words, that 63.5% of the light energy is ultimately recovered. If the energy output of this cell is used to heat water, how many 520 nm photons must be absorbed by the photovoltaic cell in order to heat 10.0 g of water from 20.0°C to 30.0°?

Ans: 1.72 1021

Category: Difficult Section: 7.2

109. The Bohr model of the hydrogen atom found its greatest support in experimental work on the photoelectric effect.

Ans: True Category: Medium Section: 7.3

110. An electron in a 3p orbital could have a value of 2 for its angular momentum quantum number (l).

Ans: True Category: Medium Section: 7.6

111. A neon atom in its ground state will be diamagnetic.Ans: True Category: Medium Section: 7.8

112. Each shell (principal energy level) of quantum number n contains n subshellsAns: True Category: Easy Section: 7.6

113. For all atoms of the same element, the 2s orbital is larger than the 1s orbital.Ans: True Category: Easy Section: 7.7

114. According to de Broglie's equation, the wavelength associated with the motion of a particle increases as the particle mass decreases.

Ans: True Category: Easy Section: 7.4

115. The frequency of the emitted light from a cesium atom is an intensive property.Ans: True Category: Easy Section: 7.2

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