CHEMISTRY 2202 FINAL EXAMINATION

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1 hemistry 2202 Final Exam June 2006 page 1 EMISTRY 2202 FINAL EXAMINATIN Monday, June 12 th, :00 am 12:00 pm June 2006 GENERAL INSTRUTINS 1. This exam consists of two sections: Section 1 Multiple hoice Items Section 2 onstructed Responses 2. Please use a blue or black ink pen to write your answers in the spaces provided on the test paper. 3. Separate the exam paper into two sections at page. For items in Section 1, circle the letter of the correct answer on the answer form provided on page The exam should be completed in a 3 hour examination period. You are permitted to use a calculator. Important reference data are provided on pages 2 and Submit all test materials to your supervisor upon completion of the exam. 6. Please attempt all items.

2 hemistry 2202 Final Exam June 2006 page 4 Section 1: Multiple hoice: ircle the letter of the correct answer on the answer form provided on page In an atom, what is the region of space that is occupied by a maximum of two electrons? A. electron cloud B. nucleus. orbital D. valence level 2. Which element is located in group 6 period 2? A. barium B. mercury. molybdenum D. oxygen 3. Which atom has an octet of valence electrons? A. helium B. nitrogen. thallium D. xenon 4. What are the valence properties of a chlorine atom? Bonding Electron(s) Lone Pair(s) Bonding apacity A B D Substance X is a shiny, electrically conductive solid that reacts violently with water. It forms a white crystalline substance when reacted with chlorine. What is the most likely electronegativity value for Substance X? A B D According to a theory of metallic bonding, what accounts for the high malleability of gold? A. covalent bonds B. free-moving valence electrons. ionic bonds D. octets of valence electrons

3 hemistry 2202 Final Exam June 2006 page 5 7. Which has the electron configuration of an argon, Ar, atom? A. bromide ion, Br B. bromine atom, Br. potassium atom, K D. potassium ion, K + 8. Which exists as a lattice of oppositely charged ions? A. uzn B. Kl. Pl 3 D. Si 2 9. What results in a covalent bond? A. electrostatic attractions among opposite poles of molecules B. mobility of electrons through valence spaces of adjacent atoms. shared attraction for a pair of valence electrons D. transfer of electrons from a metal to a nonmetal 10. Which very hard, high melting point solid consists of a network of covalently bonded atoms? A. Agl B. Br 4. Si D. SnZn 11. What is the shape around the central atom in l 2? A. bent B. linear. pyramidal D. trigonal planar 12. Which bond is most polar? A. B-N B. -. -F D. S- 13. Which molecule is nonpolar? A. 4 B. Br. 2 D. N Which is an intramolecular force? A. covalent bond B. dispersion force. dipole-dipole force D. hydrogen bond

4 hemistry 2202 Final Exam June 2006 page Which is an inorganic compound? A. l 4 B. a 3. 3 D. 16. Which liquid is more viscous than the others? A.. B. D. 17. Why are propane, propene and propyne homologous? A. they differ by a constant unit of two hydrogen atoms B. they differ by type of carbon to carbon covalent bonds. they have the same molecular shape and size D. they have the same number of carbon atoms per molecule 18. Which is an alkane? A. 6 6 B D Which could be an alicyclic alkane (cycloalkane)? A. 3 6 B D What characterizes bonding in benzene? A. alternating single and double bonds B. carbon to carbon bonds of different bond lengths. delocalized bonding electrons shared equally among ring carbons D. hydrogen atoms that lack duets of valence electrons

5 hemistry 2202 Final Exam June 2006 page Which is an isomer of 2,4-dimethylpentane? A. B.. D. 22. What is the IUPA name for this molecule? A. butylbenzene B. butylcyclohexene. propylbenzene D. propylcyclohexene 23. Which compound is correctly matched with a chemical process it can undergo? A. chloromethane cracking B. dichlorodifluoromethane hydrocarbon combustion. ethane esterification D. ethene polymerization

6 hemistry 2202 Final Exam June 2006 page In the winter of 2006, an oil tanker dumped bilge oil into the ocean off the Avalon Peninsula. Samples of the oil were separated into the many compounds on the basis of their boiling points. Which process may have been used to separate the compounds and what class of compounds should have been found in the oil? Process lass of ompounds A. addition polymerization monomers B. carbonization carbonates. fractional distillation hydrocarbons D. vitalism amines 25. Along with water, which is the product of a reaction between ethanoic acid and methanol? A N 2 B. 3 D What is the functional group of this compound? A. carbonyl B. carboxyl. ether D. ester 27. What is the functional group of this compound? A. carbonyl B. carboxyl. ether D. ester 3

7 hemistry 2202 Final Exam June 2006 page Which can undergo hydrogen bonding with molecules of similar composition? A.. l F F F F B. N D. 29. What is the name of this isotope? Fe A. iron-26 B. iron-32. iron-58 D. iron ow many neutrons are there in one atom of nickel-64? A. 28 B D ow many atoms of lithium are there in one mole of lithium-7? A. 3 B x 10 1 D x What is the molar mass of potassium hydrogen sulfate, KS 4? A g/mol B g/mol g/mol D g/mol 33. ow many moles of sodium are there in a 2.30 g sample? A mol B mol mol D mol

8 hemistry 2202 Final Exam June 2006 page What is the volume of a 0.30 mol sample of hydrogen gas, 2, at STP conditions? A L B L. 6.7 L D. 14 L 35. What is the percent composition, by mass, of P 4 S 10? A % phosphorus and 72.14% sulfur B % phosphorus and 71.43% sulfur % phosphorus and 50.87% sulfur D % phosphorus and 50.00% sulfur 36. ow many moles of fluorine gas should react to produce 0.50 mol of manganese(iii) fluoride? A mol B mol mol D. 114 mol 2Mn(s) + 3F2 (g) 2MnF3 (s) 37. What mass of oxygen gas reacts with 10.0 g of zinc to form g of zinc oxide? A g B g g D g 2Zn(s) + 2 (g) 2Zn(s) 38. What volume of chlorine gas should react with 16 L of nitrogen gas at STP conditions? N2(g) + 3 l2(g) 2 Nl3(g) A. 8.0 L B. 16 L. 32 L D. 48 L 39. A chemist added 0.15 mol of phosphorus, 0.28 mol of oxygen, and 0.52 mol of bromine to a large reaction flask and allowed a reaction to proceed until one reactant was completely consumed. P4(s) + 2 2(g) + 4 Br2(l) 4 PBr2(s) Which should be the limiting species in this reaction? A. Br 2 B. 2. P 4 D. PBr 2

9 hemistry 2202 Final Exam June 2006 page Students at XYZ Regional Academy conducted an experiment involving this reaction: u (s) + 2 AgN3(aq) 2 Ag(s) + u(n 3) 2(aq) and obtained a percent yield of 103%. They reviewed their observations for the activity and noticed that they reported seeing a deep blue ring on the filter paper containing the solid precipitate. What best accounts for the percent yield reported by the students? A. improper reading of the meniscus B. insufficient rinsing of the precipitate. loss of precipitate during transfer to the filtration funnel D. massing an insufficient amount of silver nitrate reactant 41. Solution A conducts electricity and forms a precipitate with solution B. Solution B is known to be ammonium sulfate, (N 4 ) 2 S 4. ow should solution A be classified? A. ionic and electrolytic B. ionic and non-electrolytic. molecular and electrolytic D. molecular and non-electrolytic 42. Which represents the dissociation of sodium hydrogen phosphate? A. Na2P 4(s) 2 Na(aq) + P4(aq) B (s) (aq) + 4(aq) (s) 2(aq) + 4(aq) Na P 2 Na P Na P Na P D. Na2P 4 (s) Na2(aq) + 2 (g) + P4(aq) 43. Which ionizes completely in water? A. bromomethane, 3 Br B. ethanol, 2 5. hydrogen bromide, Br D. potassium chloride, Kl 44. Which has low solubility in water? A. ammonium chloride, N 4 l B. lithium nitrate, LiN 3. potassium nitrate, KN 3 D. silver chloride, Agl 45. The mass of a crystal increases shortly after it has been added to a solution. ow should the solution be classified? A. saturated B. solvated. supersaturated D. unsaturated

10 hemistry 2202 Final Exam June 2006 page A saturated copper(ii) sulfate, us 4, solution contains excess solute at 25. A dissociation rate of mol of solute per second is detected. What is the rate of recrystallization of copper(ii) sulfate if the system is at equilibrium? A. < mol/s B. >0.050 mol/s mol/s D. The rate of recrystallization cannot be estimated. 47. What volume of mol/l potassium nitrate solution contains 0.50 mol of solute? A. 50 ml B. 100 ml L D. 5.0 L 48. Saline is an aqueous solution of sodium chloride, Nal. What mass of sodium chloride (molar mass = g/mol) is needed to make ml of mol/l saline solution? A g B g g D g 49. A solution is prepared by adding 10.0 ml of 10.0 mol/l l (aq) to 90.0 ml of water. What is true about the new solution? A. it contains fewer moles of l B. it contains more moles of l. it has a higher molar concentration D. it has a lower molar concentration 50. What is the sulfate ion concentration in a 0.10 mol/l solution of chromium(iii) sulfate, r 2 (S 4 ) 3? A mol/l B mol/l mol/l D mol/l

11 hemistry 2202 Final Exam June 2006 page 13 Name: School: hemistry 2202 Final Exam June 2006 Section 1: ircle the letter of your choice in each item. 1. A B D 18. A B D 35. A B D 2. A B D 19. A B D 36. A B D 3. A B D 20. A B D 37. A B D 4. A B D 21. A B D 38. A B D 5. A B D 22. A B D 39. A B D 6. A B D 23. A B D 40. A B D 7. A B D 24. A B D 41. A B D 8. A B D 25. A B D 42. A B D 9. A B D 26. A B D 43. A B D 10. A B D 27. A B D 44. A B D 11. A B D 28. A B D 45. A B D 12. A B D 29. A B D 46. A B D 13. A B D 30. A B D 47. A B D 14. A B D 31. A B D 48. A B D 15. A B D 32. A B D 49. A B D 16. A B D 33. A B D 50. A B D 17. A B D 34. A B D Useful Formulas and onstants m n = M n = v N n = 1 mol = 6.02 x N a n v V v = v VSTP = 22.4 L mol = i i f f actual theorectical % difference = 100% theoretical = actual yield %yield 100% theoretical yield

12 hemistry 2202 Final Exam June 2006 page 14 Name: School: Section 2 onstructed Responses omplete all items in this section. Your responses must be clear and well organized. alculated answers must demonstrate appropriate use of formulas, units, and rules for rounding/significant digits. (3) 51. By writing a complete, balanced Lewis diagram equation, predict the chemical formula of the compound formed in a reaction between aluminum and chlorine atoms. (4) 52. In terms of structure, bonding type and properties such as hardness, melting point, electrical conductivity, and solubility, describe the similarities and differences between potassium chloride and silicon carbide. (2) 53. Draw the Lewis diagram and the structural formula for 3.

13 hemistry 2202 Final Exam June 2006 page 15 Name: School: + (2) 54. Using delta notation ( δ, δ ) and arrows, indicate bond dipoles on the structural formula provided and state whether the molecule is polar or nonpolar. Br (4) 55. Provide a complete intermolecular force analysis for each compound and predict which substance has the higher boiling point. a) N 2 l b) P 2 F (2) 57. List the bonding properties of carbon that contribute to the tremendous diversity of organic compounds.

14 hemistry 2202 Final Exam June 2006 page 16 Name: School: (3) 56. Briefly describe of each of these petrochemical processes and explain how each one affects everyday life in North American society. a) fractional distillation b) addition polymerization c) cracking (8) 58. Provide the missing information in this table. Structure Name Saturated or Unsaturated 3 3 2,3-dimethyl-1-butene

15 hemistry 2202 Final Exam June 2006 page 17 Name: School: (4) 59. Provide the missing information in this table. Structure Name Functional Group propanone (2) 60. a) alculate the mass of 75 L of sulfur dioxide, S 2, at STP conditions. (2) b) alculate the number of atoms in 15 L of helium gas at STP conditions.

16 hemistry 2202 Final Exam June 2006 page 18 Name: School: (4) 61. Determine the empirical formula of a substance that is 32.00% carbon, 4.04% hydrogen, and 63.96% oxygen. (3) 62. A compound is 38.69% carbon, 9.76% hydrogen and 51.55% oxygen, and has a molar mass of g/mol. Determine the molecular formula of the compound. (3) 63. Distinguish between dissociation and molecular solvation. Provide examples to support your answer.

17 hemistry 2202 Final Exam June 2006 page 19 Name: School: (2) 64. a) alculate the volume of 14.6 mol/l phosphoric acid that is required to prepare ml of mol/l phosphoric acid solution. (2) b) With reference to the required glassware and materials, describe how to prepare the diluted phosphoric acid solution described in (a) above. 65. Excess zinc metal is reacted with ml of mol/l hydrochloric acid at STP conditions. Zn + 2 l + Znl (s) (aq) 2(g) 2(aq) (3) a) alculate the amount of hydrogen gas that should be produced at STP conditions. (1) b) The actual yield of hydrogen gas in the reaction is 516 ml. alculate the percent yield of hydrogen gas.

CHEMISTRY 2202 FINAL EXAMINATION

CHEMISTRY 2202 FINAL EXAMINATION hemistry 2202 Final Exam June 2006 page 1 EMISTRY 2202 FINAL EXAMINATIN Monday, June 12 th, 2006 9:00 am 12:00 pm June 2006 GENERAL INSTRUTINS 1. This exam consists of two sections: Section 1 Multiple