91年 - 58學士後西醫化學91化學#86891

1.What is the final product for the following reaction sequence?

(A)3-bromo-6-ethyl-4-nitrophenol (B)6-bromo-2-ethyl-4-nitrophenol(C)2-bromo-1-4-nitrobenzene (D)2-bromo-1-ethypheno1 (E)4-bromonitrotoluene

2.Please give the correct name for the following structure. (A)(R,S)-2,3-dichlorobutane (B)(2R,3S)-2,3-dichlorobutane (C)(2S,3S)-2,3-dichlorobutane (D)(2R,3R)-2,3-dichlorobutane (E)1,2-dichloroethane

3.Which of the following reagents can be used to carry out the following transformation? (A)H₂O/H⁺ (B)1.KmnO₄, 2.H₂O (C)1.Br ₂, hv, 2.H₂O (D)1.Na, 2.H₂O/H⁺ (E)NaOH

4.The final product for the reaction sequence below is (A)PhCH₂OEt (B)PhCH₂OH (C)Ph(CH₂)₂Br (D)Ph(CH₂)₂OEt (E)Ph(CH₂)₃OH

5.Which of the following compounds does not undergo both S_N1 and S_N2 reaction? (A) (B) (C) (D) (E)

6.What is the final product for the following sequence of reaction below? (A)2-methyl-1-pentanol (B)2-methylpentaneitrile (C)acetonitrile (D)2-pentanamine (E)2-bromo-2-cyano-pentanol

7.(S)(+)-Butanol shows a specific rotation at +13.52° . What is the ratio of (S)(+)-Butanol and (R)(-)-butanol when the measured rotation equals to +6.76° ? (A)(S):(R) = 4:1 (B)(S):(R) = 2:1 (C) (S):(R) = 1:2 (D)(S):(R) = 1:2.5 (E)(S):(R) = 3:1

8.Calculate the DG for the reaction, 2SO₂(g)+O₂→2SO₃(g)

$\"5ee324a79ce5a.jpg#s-52,39\"$ :SO₂=- 300.4kJ /mol;SO₃= 370.4kJ /mol (A)-70.0kJ (B)+70.7kJ (C)-670.8kJ (D)-140.0kJ (E)+140.0kJ

9.Which of the following terms best describes the pair of compound shown: (A)enantiomers (B)diastereomers (C)meso compounds (D)same compound (E)threo-erythro isomer

10.For the following reactions the major products are shown: (A)kinetic thermodynamic (B)thermodynamic kinetic (C)kinetic kinetic (D)thermodynamic thermodynamic (E)none of these

11.The number of possible dichloronitrobenzene isomers is (A)3 (B)4 (C)6 (D)8 (E)9

12.Which of the following compounds has a double bond that is conjugated with the p system of the benzene ring? (A)p-Benzyltoluene (B)2-Phenyl-1-decene (C)3-Phenylcyclohexene (D)3-Phenyl-1,4-pentadiene (E)None of these

13.Consider the following statements concerning the effect of a trifluromethyl group-CF₃, on an electrophilic aromatic substitution. Which of these statements is (or are) correct? 1.The CF₃ group will activate the ring. 2.The CF₃ group will deactivate the ring. 3.The CF₃group will be a meta director. 4.The CF₃group will be an ortho, para director. (A)1,3 (B)1,4 (C)2,3 (D)2,4 (E)3,4

14.All the following groups are activating ortho, para directors when attached to a benzene ring EXCEPT O (A) (B)－OCH₃ (C)－C1 (D)－N(CH₃)₂ (E)None of these

15.The ¹H nmr spectrum of acetone consists of a singlet with a chemical shift of 2.07 ppm. What was the spectrometer frequency of the instrument used if this chemical shift equaled 186Hz? (A)60MHz (B)90MHz (C)100MHz (D)120MHz (E)Need more information to determine

16.The following problem refers to the ¹H nmr spectrum of CH₃CH₂OCH₂OCH₂CH₃. (A)12 (B)5 (C)4 (D)3 (E)6

17.The relationship between magnetic field strength and the energy difference between nuclear spin states is: (A)The are independent of each other. (B)They are directly proportional. (C)They are inversely proportional. (D)They relationship varies from molecule to molecule. (E)None of these.

18.An infrared spectrum exhibits a broad band in the 3000 to 3500cm^-1 region and a strong peak at 1710cm^-1 . Which of the following substances best fits the data? (A)C₆H₅CH₂CH₂OH (B)C₆H₅CH₂COOH (C) (D) (E)

19.Which (if any) of the following would not be classified as an organometallic substance? (A)Triethylaluminum (B)Ethylmagnesium iodide (C)Potassium tert-butoxide (D)None of these(all are organometallic compounds) (E)All of these.

20.Rank the following species in order of increasing polarity of the carbon-metal bond (lest®most polar): (A)C < A < B (B)B < A < C (C)A < C < B (D)B < C < A (E)A < B < C

21.How many electrons in an atom can have of the following quantum number or sublevel designations? (choosing the correct answers) (I) n = 2，I = 1. (II) 3d. (III) 4s. (IV) 4p. (V) n = 3. I = 1，m₁ = 1. (VI) n=5, I=3. (A)(I) + (II) = 15e^-(B)(III) + (IV) = 8e^-(C)(V) + (VI) = 15e^-(D)(I) + (II) + (V) = 10e^- (E)(II) + (IV) + (VI) = 28e^-

22.Of the following sets of four quantum numbers, identify the ones that can exist for an electron in an atom? (A) n = 1，I = 1，m1 = 0，ms = 1/2. (B) n = 2，I = 0，m1 = ±1，ms = 1/2. (C) n = 3，I = 3，m1 = ±3，ms = -1/2. (D) n = 4，I = 3，m1 = ±2，ms = 1/2. (E) n = 4，I = 4，m1 = -1，ms = 1/2.

【已刪除】複選題

23.How many valence electrons in an element can have for each of the following species? (choosing the correct answers) (I)P³⁺ (II)Rh²⁺ (III)Co⁴⁺ (IV)Mn³⁺ (V)Ni²⁺ (VI)Si²⁺ (VII)Sb (VIII)B¹⁺ (AB)(I) + (III) = 8e^-(AC)(II) + (VI) = 8e^-
(AD)(III) + (VII) = 9e^-(AE)(I) + (IV) + (VIII) = 6e^-(BC)(II) + (V) + (VII) = 18e^-
(BD)無答案

24.Which of the following statements is not correct? (A)According to the VSEPR theory, the I3- molecule is predicted to be linear. (B)According to the VSEPR theory, the InF4 1- molecule is predicted to be tetrahedral. (C)According to the VSEPR theory, the GeBr 3 1- molecule is predicted to be trigonal planar (D)According to the VSEPR theory, the C1I3 molecule is predicted to be T-shaped. (E)According to the VSEPR theory,TeS3 2- molecule is predicted to be pyramidal.

25. Suppose the hypothetical set of quantum numbers:
n = 1, 2, 3, ……
l = 0, 1, 2, 3, …… , n–1
mₗ = 1
s = 1/2, –1/2
then which of the following statements is not correct?(A) There is one s orbital, one p orbital, and one d orbital.(B) The atomic number of the first element in the d orbital-filler is 12.(C) There are two transition elements in the first period.(D) The atomic number of the first inert gas is 2.(E) If one element has the atomic number 14, then its electron configuration is 1s²2s²2p³3s²3p².

26.Arrange in decreasing order of stability of the following four isomers. (I)cis-1-chloro-2-methylcyclohexane (II)trans-1-chloro-2-methylcyclohexane (III)cis-1-chloro-3-methylcyclohexane (IV)trans-1-chloro-3-methylcyclohexane (A)(II) > (III) > (I) > (IV) (B)(I) > (II) > (IV) > (III) (C)(III) > (II) > (IV) > (I) (D)(IV) > (II) > (I) > (III) (E)none of the above.

27.Diastereomers have the same (A)melting point. (B)reaction rate toward optically active reagent. (C)molecular weight. (D)stereochemistry at each chiral center. (E)specific rotation.

28.Which of the following statements is correct? (A)A structure with two chiral centers will always give rise to four stereoisomers (B)Molecules that contain chiral carbons must be optically active compounds. (C)Equimolar mixtures of two enantiomers are called racemate. (D)Distereomers have same physical properties. (E)none of the above.

29.Who characterized alpha, beta and gamma radiation? (A)Thomson (B)Einstein (C)Rutherford (D)Heisenberg (E)Bohr

30.Of the following sets of four quantum numbers, identify the ones that can exist for an electron in an atom? (A)(5, 4, 5, +1/2) (B)(2, 2, -1, +1/2) (C)(3, 2, 2, +1/2) (D)(6, 7, 0, +1/2) (E)(2, 0, -2, +1/2)

31.How many constitutional isomers are there for C5H11Br? (A)3 (B)7 (C)8 (D)10 (E)11.

32.Which of the following statements correctly describes an achiral molecule? (A)The molecule has a nonsuperimposable mirror image. (B)The molecule exhibits optical activity when it interacts with plane-polarized light. (C)The molecule has an enantiomer. (D)The molecule might be a meso form. (E)None of the above.

33.Which of the following molecules has the highest bond order? (A)BN (B)CO (C)NO (D)Ne₂ (E)F₂

34.According to the VSEPR theory, which of the following statements is correct? (A) The expected geometry of TeO₃^2- is trigonal planar. (B) The expected geometry of SbBr₄^3- is tetrahedral. (C) The expected geometry of SeS₂^4-is bent. (D) The expected geometry of BiCl₃is pyramidal. (E) The expected geometry of SnI₄^2- is square planar.

複選題
35.Which of the following statements is correct? (A)In O₂, O₂^2- , O₂^-, and O₂⁺ species, only the O₂^2- molecule is diamagnetic. (B)The stability decreases in the order O₂⁺ > O₂ > O₂^- >O₂^2- (C)The dissociation energy of N₂ is larger than that of N₂⁺ , while the dissociation energy of C₂⁺ is smaller than that of C₂. (D)In Mn²⁺, Cr³⁺, Hg²⁺ , V ³⁺, Ni²⁺, and La³⁺ six transition metal ions, only Mn²⁺, V ³⁺, and La³⁺ are paramagnetic. (E)The atom size increases in the order K⁺ > Cl^- > S^2- , while the atom size of Au+ is larger than that of Au³⁺ .

36.Which of the following atoms is paramagnetic? (A)Cd (B)Tl^1- (C)Nb¹⁺ (D)Ni (E)Ru¹⁺

複選題
37.Which of the following statements is not true? (A)trans-1,3-dimethylcyclohexane is more stable than cis –1,3-dimethylcyclohexane. (B)trans-1,2-dimethylcyclohexane is more stable than cis–1,2-dimethylcyclohexane. (C)trans-1,4-dimethylcyclohexane is more stable than cis–1,4-dimethylcyclohexane. (D)trans-1,2-dimethylcyclohexane is more stable than cis–1,3-dimethylcyclohexane. (E)trans-1,2-dimethylcyclohexane is less stable than cis–1,3-dimethylcyclohexane.

38.The approximate pK_a of NH₃ is 36; that of C₂H₅OH is 16. From this information, which (if any) of the following conclusion is (or are) correct? (A)The conjugate base of C₂H₅OH is stronger. (B)The conjugate base of NH₃ is stronger. (C)C₂H₅OH is a weaker acid than NH₃ (D)None of the these is correct. (E)All of these are correct.

39.The activation energy(Eact) of a give reaction is unrelated to which of the following parameters? (A)The rate of the slowest step of a multistep reaction. (B)The rate of the overall teaction. (C)The heat absorbed or given off by the reaction (DH) (D)The stability of the transition state. (E)None of these.

40.Which of the following is least able to serve as a nucleophile in a chemical reaction? (A)Br^- (B)OH^-(C)NH₃ (D)CH₃⁺ (E)I^-

41.Thiols are alcohol analogs in which the oxygen has been replaced by sulfur (e.g., CH₃SH). Given the fact that the S-H bond is less polar than the O-H bond, which of the following statements comparing thiols and alcohols is correct? (A)Hydrogen bonding forces are weaker in thiols. (B)Hydrogen bonding forces are stronger in thiols (C)Hydrogen bonding forces would be the same. (D)No comparison can be made without additional information. (E)None of these.

42.Rank the transition states which occur during the following reaction steps in order of increasing stability (least→most stable): (a)CH₃ - OH₂⁺→CH₃⁺ +H₂O (b)(CH₃)₃C - OH₂⁺→(CH₃)₃C ⁺ + H₂O (c)(CH₃)₂CH - OH₂⁺→(CH₃)₂CH⁺ + H₂O (A)a < b < c (B)b < c < a (C)a < c < b (D)b < a < c (E)c < b < a

43.An alkane with a molecular formula C₆H₁₄reacts with chlorine in the presence of light and heat. Four constitutionally isomeric monochlorides of molecular formula C₆H₁₃Cl are formed (along with a mixture of dichlorides, trichlorides, and so on). What is the most reasonable structure for the starting alkane? (A)CH₃CH₂CH₂CH₂CH₂CH₃ (B)(CH₃)₂CHCH₂CH₂CH₃ (C)CH₃CH(CH₂CH₃)₂ (D)(CH₃)₃CCH₂CH₃ (E)(CH₃)₂CHCH(CH₃)₂

44.Carboxylic acids exist in the vapor state as: (A)Monomeric species (B)Cyclic esters (C)Cyclic dimers (D)Cyclic trimers (E)None of these

45.The product from the reaction of 1-pentene with Cl₂ in H₂O is named: (A)1-Chloro-2-pentanol (B)2-Chloro-2-pentanol (C)1-Chloro-1-pentanol (D)2-Chloro-1-pentanol (E)none of these

46.In the traction of a reagent such as HBr with an alkene, the frist step of the reaction is the to ______the alkene.(A)Fast addition of an electrophile(B)Fast addition of a nuclephile(C)Slow addition of an electrophile(D)Slow addition of a nuclephile(E)none of these

47.Markovnikov’s rule “works” because: (A)The most stable transition state is the one leading to the more substituted carbocation. (B)The nucleophile adds during the second step of the ionic reaction. (C)The electrophile adds to the less substituted end of the double bond. (D)All of these are true. (E)All of these are not true.

48.Treatment of 2-methyl-2-butene with HBr in the presence of peroxide yields (A)A primary alkyl bromide (B)A secondary alkyl bromide (C)A tertiary alkyl bromide (D)A vicinal dibromide (E)None of these

49.The strongest evidence for the formation of a bridged bromonium ion as an intermediate in the addition of Br2 to an alkene is: (A)Markovnikov’s rule (B)Zaitsev’s rule (C)The regioselectivity of the reaction (D)The stereospecificity of the reaction (E)None of these

50.A compound having a molecular formula of C₂₀H₃₆is inert to catalytic hydrogenation. Which of the following statements is true? (A)The substance has at least one double bond and two rings. (B)The substance is acyclic (i.e., no rings are present) (C)The substance has two rings. (D)The substance has three rings. (E)None of these.

51.The bimolecular subsittution reaction CH₃Br + OH^- →CH₃OH + Br^-is represented by the kinetic equation: (A)Rate = k[CH₃Br]² (B)Rate = k[CH₃Br][OH^-] (C)Rate = k[CH₃Br] + k[OH^- ] (D)Rate = k/[CH₃Br][OH^- ] (E)Rate = k[CH₃Br]2 + k[OH^-]

52.The solvoysis reactions of optically active halides generally proceed with (A)Complete racemization (B)Partial racemization (C)complete retention of configuration (D)Complete inversion of configuration (E)None of these

53.Which of the following statements pertaining to an S_N2 reaction are true? 1.The rate of reaction is independent of the concertration of the nucleophile.2.The nucleophile attacks carbon on the side of the molecule opposite the group being displaced.3.The reaction proceeds with simultaneous bond formation and bond rupture.4.Partial racemization of an optically active substrate results. (A)1,4 (B)1,3,4 (C)2,3 (D)1,3 (E)All

54.Which of the following phrases are not correctly associated with SN1 reactions? 1.Rearrangements possible 2.Rate affected by solvent polarity 3.Strength of nucleophile important in determining rate 4.Reactivity series tertiary > secondary > primary 5.Proceed with complete inversion of configuration (A)3,5 (B)1,5 (C)2,3,5 (D)3 only (E)4,5

55.Which of the following statements is true concerning pK_a? (A)The larger the pK_a value, the weaker the acid. (B)Strong acids have small pK_a values. (C)pK_a = -log K_a (D)All the statements are correct. (E)All the statements are incorrect.

56.Referring to the following equilibrium (R=alkyl group)(A)K < 1 ; the equilibrium would lie the left. (B)K > 1 ; the equilibrium would lie the right. (C)K = 1 ; equal amounts of all species would be present. (D)Not enough information is given; the structure of R must be known. (E)None of these

57.Which alkyne yields butanoic acid (CH₃CH₂CH₂CO₂H) as the only organic product upon treatment with ozone followed by hydrolysis? (A)1-Butyne (B)4-Octyne (C)1-Pentyne (D)2-Hexyne (E)None of these ..

58.Which of the following produces a significant amount of acetylide ion on reaction with acetylene? (A)Conjugate base of CH₃OH (pK_a16) (B)Conjugate base of H₂ (pK_a35) (C)Conjugate base of H₂O (pK_a16) (D)Both {A} and {C} (E)Both {A} and {B}

59.Hydrogenation of cyclohexene releases 120kJ/mol of heat. Which of the following most likely represents the observed heat of hydrogenation of 1,3-cyclohexadiene? (A)232kJ/mol (B)239kJ/mol (C)247kJ/mol (D)120kJ/mol (E)142kJ/mol

60.Arrange the following intermediates in order of decreasing basicity (strongest→weakest): (A)B > A > D > (B)D > A > B > C (C)C > D > A > B (D)C > B > D >A (E)D > C >B >A

61.Give the major product of the following reaction: [E]-2-pentence+ CH₂I₂/Zn(Cu)→ ? (A)cis-1-Ethyl-2-methylcyclopropane (B)trans-1-Ethyl-2-methylcyclopropane (C)1-Ethyl-1-methylcyclopropane (D)An equimolar mixture of product {A} and {B}(E)None of these

62.Which of the following would yield a secondary alcohol after the indicated reaction, followed by aqueous hydrolysis if necessary? (A)LiAlH₄ + a ketone (B)CH₃CH₂MgBr + an aldehyde (C)2-Butene + mercury(II)acetate, then NaBH₄, HO (D)All of these (E)None of these

63.Which of the esters shown, after reduction with LiAlH4 and aqueous workup, will yield two molecules of only a single alcohol? (A)CH₃CH₂CO₂CH₂CH₃ (B)C₆H₅CO₂C₆H₅ (C)C₆H₅CO₂CH₂C₆H₅ (D)None of these (E)All of these

64.For the following reaction, select the statement which best describes the situaton.

RCH₂OH + (C₅H₅N)₂CrO₃→

(A)The alcohol is oxidized to an acid, and the Cr (VI) is reduced. (B)The alcohol is oxidized to an aldehyde, and the Cr (VI) is reduced. (C)The alcohol is reduced to an aldehyde, and the Cr (III) is oxidized (D)The alcohol is oxidized to a ketone, and the Cr (VI) is reduced. (E)The alcohol is oxidized to an acid, and the Cr (III) is reduced.

65.Which of the following alcohols gives the best yield of diakyl ether on being heated with a trace of sulfuric acid? (A)1-Pentanol (B)2-Pentanol (C)Cyclopentanol (D)2-Methyl-2-butanol (E)2-Ethyl-propanol

66.The most effective pair of reagents for the preparation of tert-butyl ethyl ether is: (A)Potassium tert-butoxide and ethyl bromide (B)Potassium tert-butoxide and ethanol (C)Sodium ethoxide and tert-butyl bromide (D)tert-Butyl alcohol and ethyl bromide (E)None of these

67.Heating a particular ether with HBr yielded a single organic product. Which of the following conclusions may be reached? (A)The reactant was a methyl ether. (B)The reactant was a symmetrical ether. (C)The reactant was a cyclic ether. (D)Both {B}and {C} are correct (E) Both {A} and {B} are correct

68.In the ¹H NMR spectrum of CH₃CH₂CH=CH₂, how many signals are expected? (A)3 (B)4 (C)5 (D)6 (E)7

69.Ionization energies are (A)always negative (B)always positive (C)usually positive but sometimes negative (D)usually negative but sometimes positive (E)usually zero

70.Rank the following in order of increasing size:Cl, Cl⁺ , Cl^- (A)Cl < Cl⁺ < Cl^-(B)Cl < Cl - < Cl⁺ (C)Cl^- < Cl < Cl⁺ (D)Cl⁺ < Cl^- < Cl (E)Cl⁺ < Cl < Cl^-

71.When carbon bonds to chlorine, the bond will be ___ and ___ atom bears a partial negative charge. (A)nonpolar, neither (B)polar, the carbon (C)polar, the chlorine (D)nonpolar, the carbon
(E)nonpolar, the chlorine

72.Which of the following is (or are) the rate law for a reaction that is first order in oxygen? (A)rate = k[NO₂] (B)rate = k[NO₂][O₂] (C)rate = k[NO₂] ² / [O₂] (D)rate = k[NO₂] ² / ([O₂[N₂]]) (E)All of the above

73.When a catalyst is added to a reaction system, (A)the equilibrium position is changed (B)the enthalpyis changed (C)the rate is changed (D)all of the above (E)none of the above

74.Which of the following is not aromatic? (A)pyridine (B)furan (C)cyclobutadiene (D)benzene (E)annulene

75.Which sub-shell can hold the greatest number of electrons? (A)3d (B)3p (C)4p (D)5p (E)5s

76.In the Lewis structure of ozone, the central oxygen atom has (A)1 lone pair and 4 bonding pairs of electrons (B)1 lone pair and 2 bonding pairs of electrons (C)2-lone pair and 2 bonding pairs of electrons (D)1-lone pair and 3 bonding pairs of electrons (E)2-lone pairs of electrons

77.What type of orbitals best describes the bond between the two oxygen atoms in H-O-O-SO3? (A)sp-sp (B)sp² -sp ² (C)sp³ -sp ³ (D)s-s (E)2_px-2_px

78.Condider the following reaction: 3H₂(g) + N₂(g) « 2NH₃(g). All of the following will lead to the production of more NH3(g) EXCEPT (A)removal of NH₃(g) (B)a decrease in the volume of the container (C)an increase in pressure by adding N₂(g) (D)an increase in pressure by adding argon (E)addition of H₂(g)

79.The conjugate acid of ammonia is (A) NH^-₂ (B)NH₂OH (C) NH⁺ ₄ (D)HO^- (E)NH₃

80.Which of the following conditions will result in a spontaneous reaction at all temperatures? (A)△H < 0, △S < 0 (B)△H > 0, △S < 0 (C) △H < 0, △S > 0 (D)△H > 0,△S > 0 (E)△H > 0, △S = 0

91年 - 58學士後西醫化學91化學#86891

試卷資訊

選擇題 (80)

申論題 (0)