Name:_______________ Student number:__________________ Department:______________ (單選題共 33 題,每題 4 分) 1. How many electrons are transferred in the following reaction? Cr2O72- + 14H+ + 6Cl– 2Cr3+ + 3Cl2 + 7H2O a) 2 b) 4 c) 6 d) 8 e) none of these 2. When the equation for the following reaction in basic solution is balanced, what is the sum of the coefficients? MnO4–(aq) + CN–(aq) MnO2(s) + CNO–(aq) a) 13 b) 8 c) 10 d) 20 e) 11 3– 5. Consider the galvanic cell shown below (the contents of each half-cell are written beneath each compartment): The standard reduction potentials are as follows: 3. E =– 0.73 V Br2(aq) + 2e– 2Br– E = +1.09 V What is E for this cell? a) 1.82 V 4. Cr3+ + 3e- Cr(s) b) 0.36 V c) 4.75 V d) 1.79 V e) 4.40 V What is the value of E for this cell at 25 C? a) 2.21 V b) 1.76 V c) 2.12 V d) 1.88 V e) 0.59 V 5. Which of the following statements about this cell is false? a) This is a galvanic cell. b) Electrons flow from the Pt electrode to the Cr electrode. c) Reduction occurs at the Pt electrode. d) The cell is not at standard conditions. e) To complete the circuit, cations migrate into the left half-cell and anions migrate into the right half-cell from the salt bridge. 1 6. A cell is set up with copper and lead electrodes in contact with CuSO4(aq) and Pb(NO3)2(aq), respectively, at 25 C. The standard reduction potentials are: Pb2+ + 2e– Pb E =– 0.13 V Cu2+ + 2e– Cu E = +0.34 V If sulfuric acid is added to the Pb(NO3)2 solution, forming a precipitate of PbSO4, the cell potential: a) increases b) decreases 7. c) is unchanged d) c an’ tt e l lwhatwi l lhappe n A galvanic cell is constructed with copper electrodes and Cu2+ in each compartment. In one compartment, the [Cu2+] = 1.0 10–3 M and in the other compartment, the [Cu2+] = 2.0 M. Calculate the potential for this cell at 25 C. The standard reduction potential for Cu2+ is +0.34 V. a) 0.44 V b) – 0.44 V c) 0.098 V d) – 0.098 V e) 0.78 V 8. Using the following data calculate the Ksp value at 25 C for PbSO4(s). a) 2.57 x 10105 b) 3.89 x 10–105 c) 5.9 x 107 d) 1.7 x 10–8 e) None of these is within 5% of the correct answer. 9. Copper is electroplated from CuSO4 solution. A constant current of 4.00 amp is applied by an external power supply. How long will it take to deposit 1.00 x 102 g of Cu? The atomic mass of copper is 63.546. a) 21.1 h b) 10.0 min c) 1.60 days d) 11.2 s e) 2.91 h 10. In which of the following cases can E be equal to zero? a) In any cell at equilibrium. b) In a concentration cell. c) E can never be equal to zero. d) Choices a and b are both correct. 11. For a reaction in a voltaic cell both H and S are positive. Which of the following statements is true? a) E cell will increase with an increase in temperature. b) E cell will decrease with an increase in temperature. c) E cell will not change when the temperature increases. d) G > 0 for all temperatures. e) None of the above statements is true. 2 12. What is the electron configuration of the Co(II) ion? a) [Ar]4s23d5 b) [Ar]4s24d2 c) [Ar]4s23d7 d) [Ar]3d7 e) none 13. Which of the following coordination compounds will form a precipitate when treated with an aqueous solution of AgNO3? a) [Cr(NH3)3Cl3] b) [Cr(NH3)6]Cl3 c) [Cr(NH3)Cl]SO4 d) Na3[Cr(CN)6] e) Na3[CrCl6] 14. Which of the following are structural isomers? a) I, III I. coordination isomers II. III. geometric isomers IV. optical isomers b) II, IV c) I, III, IV linkage isomers d) II, III e) I, II 15. Give the number of geometrical isomers for the octahedral compound [MA2B2C2], where A, B, and C represent ligands. a) 1 b) 2 c) 3 d) 5 e) none of these 16. Which of the following is paramagnetic? a) Zn(H2O)62+ b) Co(NH3)63+ (strong field) c) Cu(CN)32– d) Mn(CN)63–(strong field) e) none of these 17. Fluoride ion ranks low in the spectrochemical series and produces a weak crystal field in complex ions. Based on this information, predict the number of unpaired electrons in CoF63–. a) 0 b) 1 c) 2 d) 3 e) 4 18. Which transition metal can exist in all oxidation states from +2 to +7? a) copper b) vanadium c) chromium d) iron e) manganese 19. Which of the following statements concerning the complex ion Co(en)2Cl2+ is true? (en = ethylenediamine, NH2CH2CH2NH2)? a) The complex ion contains Co(I). b) The complex ion exhibits cis and trans geometric isomers, but no optical isomers. c) The complex ion exhibits two geometric isomers (cis and trans) and two optical isomers. d) Since en is a strong field ligand (large ), the complex ion is paramagnetic. e) The geometric isomers of the complex ion have identical chemical properties. 20. Calculate the total number of unpaired electrons in the following complex ions: Zn(OH2)62+, Ni(CN)42–(square planar), Co(NH3)63+ (strong field). a) 0 b) 1 c) 2 d) 3 e) 4 3 21. Which of the following is true about coordination complexes? a) The metal is a Lewis base and the ligands are Lewis acids. b) Only complexes with coordination number six are found in nature. c) When the ligands approach a transition metal ion in an octahedral field, the dxz, dyz, and dxy atomic orbitals are affected the least by the ligands. d) None of the above is true. e) All of the above are true. 22. The complex ion Co(NH3)62+ (three unpaired electrons) is classified as: a) weak field b) strong field c) no way to tell 23. Name the following: a) n-heptane b) 2-methyl-2-ethylbutane c) 3,3-dimethylpentane d) 2,2-diethylpropane 24. How many isomers of C6H14 are there? a) 1 b) 2 c) 3 d) 5 e) 6 25. How many isomers are there with the formula C2H2Br2? Include both structural and geometric isomers. a) 2 b) 3 c) 4 d) 5 e) 6 26. Which of the following, upon reacting with oxygen, would form the greatest amount of carbon dioxide? a) n-pentane b) isopentane c) neopentane d) Two of the above would form equal amounts. e) All (a-c) of the above would form equal amounts. 27. Name the following: a) 1-hexyne b) 2-ethynyl butane d) 3-methyl-1-pentyne 28. c) 2-ethyl-3-butyne e) 3-methyl-4-pentyne Name the following: a) 2-chloro-3-chloro-cis-2-butene b) 2,3-dichloro-cis-2-butene c) 2,3-dichloro-trans-2-butene d) 1-chloro-1-methyl-2-chloro-propene e) 2,3-dichloro-1-methyl-propene 29. Which of the following types of compounds lacks an sp2-hybridized carbon center? a) aldehydes b) ketones c) alcohols d) alkenes e) benzene 4 30. The oxidation of secondary alcohols results in a) ketones. b) secondary alcohols. c) aldehydes. d) esters. e) ethers. 31. Which of the following is optically active (i.e., chiral)? a) HN(CH3)2 b) CH2Cl2 c) 2-chloropropane d) 2-chlorobutane e) 3-chloropentane 32. Which of the following monomers are used to produce the polymer: a) I b) II c) III d) I and III e) II and III 33. The overall shape of a protein is maintained by a) hydrogen bonding. b) ionic bonds. c) dipole-dipole bonding. d) covalent bonds. e) all of these 5