topper package chemistry-xii unit alkyl halides
TRANSCRIPT
Topper Package chemistry-XII Permutation and CombinationsAlkyl Halides & Aryl Halides
50
MULTIPLE CHOICE QUESTIONSTOPIC (1) PREPARATION OF ALKYLHALIDE & PHYSICAL PROPERTIES
1. The boiling points of alkyl halides and theirparent hydrocarbons (RH) are in the order(a) RH > RI > RBr > RCl > RF(b) RI > RBr > RCl > RF > RH(c) RH > RF > RI > RBr > RCl(d) none of these
2. How many trichloro ethanes would be producedwhen 1, 1-dichloroethane reacts with chlorine(a) 1 (b) 2(c) 3 (d) 4
3. Best yield of alkyl halide R X is formed in2 2 2RCO Ag X RX CO AgX when 2X is:
(a) 2Cl (b) 2Br(c) 2I (d) 2F
4. Iodoform can be prepared from all except:(a) ethyl methyl ketone(b) isopropyl alcohol(c) 3-methyl-2-butanone(d) isobutyl alcohol
5. Which branched chain isomer of the hydrocar-bon with molecular mass 72u gives only one iso-mer of mono substituted alkyl halide?(a) Tertiary butyl chloride(b) Neopentane(c) Isohexane(d) Neohexane
6. The reaction conditions leading to the best yieldsof C2H5Cl are:(a) C2H6 (excess) + Cl2 UVlight
(b) C2H6 + Cl2 dark
roomtemperature
(c) C2H6 + Cl2 (excess) UVlight
(d) C2H6 + Cl2 UVlight
7.
(a) (b)
(c) (d)
8. Which of the following is added to chloroform ina small quantity before it is bottled for sale?(a) CH3OH (b) C2H5Cl(c) C2H5OH (d) AgNO3
TOPIC (2) CHEMICAL PROPERTIES9. The structure of the major product formed in the
following reaction is Cl
I
NaCNDMF
(a)CN
CN(b)
Cl
INC
(c)Cl
CN(d)
CN
I
10. A mixture of 1-chloropropane and 2-chloropropane when treated with alcoholic KOH,gives(a) prop-1-ene (b) prop-2-ene(c) isopropylene (d) both a & b
11. Identify C in the series,
alc. KOH NBS alc. KC N3 7C H I A B C
(a) 3 2( )CH CH CN (b) 2 2CH CH CH CN
(c) Br CH CH CN (d) 2CH CH CHCN|Br
12. The organic chloro compound, which showscomplete stereochemical inversion during a
2NS reaction, is(a) 3 2( )CH CHCl (b) 3CH Cl(c) 2 5 2( )C H CHCl (d) 3 3( )CH CCl
13. Vicinal and gem dihalides can be distinguishedby(a) aqueous KOH (b) alcoholic KOH(c) Zn dust (d) none of these
14. 3AgNO does not give precipitate withchloroform because(a) 3CHCl is insoluble in water(b) 3CHCl does not ionise in water
Unit6
ALKYL HALIDES &ARYL HALIDES
Topper Package chemistry-XII Permutation and CombinationsAlkyl Halides & Aryl Halides
51
(c) 3CHCl is an organic compound(d) 3AgNO is insoluble in 3CHCl
15. The final product formed by distilling ethylalcohol with excess of Cl2 and Ca OH 2( ) is(a) CH CHO3 (b) CCl CHO3(c) CHCl3 (d) CH O3 2( )
16. The end product (B) in the following sequence of
reactions is H O HKCNCH Cl A B2 /3
(a) CH COOH3 (b) HCOOH
(c) CH NH3 2 (d) CH COCH3 3
17. Which one of the following is most reactivetowards nucleophilic substitution reaction?
(a) CH CH Cl2 (b) C H Cl6 5
(c) CH CH CH Cl3 (d) ClCH CH CH2 2 .
18. In 1SN (substitution, nucleophilic, unimolecular)reaction, the racemization takes place, it is dueto(a) inversion of configuration(b) retention of configuration(c) conversion of configuration(d) both A and B.
19. Grignard reagent is not prepared in aqueousmedium but prepared in ether medium, because(a) the reagent is highly reactive in ether(b) the reagent does not react with water(c) the reagent becomes inactive in water(d) the reagent reacts with water.
20. Tertiary alkyl halides are practically inert tosubstitution by 2SN mechanism because of(a) insolubility (b) instability(c) inductive effect (d) steric hindrance
21. In which of the following reactions, the productis an ether?(a) C H CH COCl6 6 3 / anhydrous AlCl3(b) C H Cl2 5 + aq. KOH
(c) C H C H COCl6 6 6 5 /anhydrous AlCl3(d) C H Cl C H ONa2 5 2 5
22. Phosgene is a common name of(a) mixture of CO2 and Cl2(b) POC 3l(c) carbonyl chloride(d) carbon tetrachloride.
23. Arrange the following halides in the decreasingorder of
NS 1 reactivity
(I) CH CH CH Cl3 2 2 (II) CH CHCH Cl CH2 3( )
(III) CH CH CH Cl CH3 2 3( )(a) I > II > III (b) II > I > III(c) II > III > I (d) III > II > I
24. End product of following sequence of reaction is:
Br 3 23 /O H ONH BaOA B C
(a) O (b) OH
(c) O (d)HOOC COOH
25. In the following reaction final product is
Br
NaIacetone
X
(a)
I
X
(b) I
X
(c) both (a) and (b) (d) none of these26. How many chiral compound are possible on
monochlorination of 2-methyl butane?(a) 2 (b) 4(c) 6 (d) 8
27. Which of the following is the major product ofthe following reaction?
(a)
(b)
Topper Package chemistry-XII Permutation and CombinationsAlkyl Halides & Aryl Halides
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(c)
(d)
28. CH3 – Br + Nu– CH3 – Nu + Br–
The decreasing order of the rate of the abovereaction with nucleophiles (Nu–) A to D is:[Nu– = (A) PhO–, (B) AcO–, (C) HO–, (D) CH3O](a) D > C > A > B (b) D > C > B > A(c) A > B > C > D (d) B > D > C > A
29. In Finkelstein Reaction, which reactants areused(a) NaI + C2H5OH (b) NaF + acetone(c) NaBr + CH3OH (d) NaI + acetone
30. Racemic mixture is obtained due to the haloge-nation of(a) isopentane (b) n-pentane(c) neopentane (d) both (1) and (2)
31. The reaction of SOCl2 on alkanols to form alkylchlorides gives good yields because(a) alkyl chlorides are immiscible with SOCl2
(b) the reaction does not occur via intermediateformation of an alkyl chlorosulphate
(c) alcohol and SOCl2 are soluble in water(d) the other products of the reaction are gas-
eous and escape out
32. For CH3Br + OH– CH3OH + Br– the rate ofreaction is given by the expression(a) rate = k[CH3Br](b) rate = k [OH–](c) rate = k [CH3Br] [OH–](c) rate = k[CH3Br]0 [OH–]0
33. Consider the following reactions, which are car-ried out at the same temperature.
EtOH3 3CH Br OH CH OH Br .......(i)
DMSO3 3CH Br OH CH OH Br .......(ii)
Which of the following statement is correct aboutthese reactions.(a) Both the reactions take place at the same
rate(b) The first reaction takes place faster than
second reaction(c) The second reaction takes place faster than
first reaction(d) Both the reactions take place by SN1 mecha-
nism
34. Which of the following is the example of SN2 re-action?(a)
(b)
(c)(d)
35. Which of the correct reaction coordinate diagramfor the following solvolysis reaction?
(a) (b)
(c) (d)
36. CH – CH – C (Br) CH 3 3
H3C CH3
MeO K– +
X Major
Y MajorEt COK3
X and Y are respectively:
(a)CH3
CH3
C CCH3
CH3and C C
H
H(C ) CH2H3
CH3
(b) CH3
CH3
C C
CH3
CH3andC C
H
H(C ) CH2H3
CH3
(c)CH3
CH3
C C
CH3
CH3and C C
C H2 5 CH3
C H2 5 C H2 5
(d)H
HC C
CH3
(CH3)3and C C
CH3 CH3
CH3CH3
Topper Package chemistry-XII Permutation and CombinationsAlkyl Halides & Aryl Halides
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37. The dehydrobromination of 2-bromobutane givesCH3CH = CHCH3. The product is:(a) Hoffmann product(b) Saytzeff product(c) Hoffmann-Saytzeff product(d) Markownikoff product
38. alc.KOHBr
A
A may be:(a) (b)
(c) (d) All of these
39.
Br
CHCH3 CH CH3
CHO
CCH3
OHCC
H
CH3
Path of the reaction mechanism:(a) E1 (b) E2
(c) E1CB (d) both E1 & E2
40. Consider the following sequence of reaction.2 3 2
3
NaNH (excess) CH CH Br3 2
NH (I)CH CHBrCH Br (A) (B)
The two products (A) and (B) are respectively
(a) 3CH C CH and 3 2 3CH CH C CCH
(b) 3CH C CNa and 3 2(CH ) CHC CH
(c) 3CH C CNa and 3 2 3CH CH C CCH
(d) 3CH C CH and 3 2 3CH CH CH CHCH41. A compound (X), C4H8Cl2, on hydrolysis with aque-
ous KOH gives a product (Y) which on heatingwith I2 and dilute NaOH gives a yellow precipi-tate of iodoform. The compound (X) is expectedto be:(a) CH3CH2CH2CHCl2(b) CH3CH2CCl2CH3
(c) CH3CH2CHClCH2Cl(d) ClCH2CH2CH2CH2Cl
Y = Br2/CHCl3
42. HBr H
F+ NaI (1 mole) 2Acetone
SN Major(A) ;
Major product of this reaction is:
(a) HI H
F (b) IH H
F
(c) H
Br HI (d) H
Br IH
43. Rank the following in order of decreasing rate ofsolvolysis with aqueous ethanol (fastest slow-est)
(1) H C2 C Br
CH3(2)
CH3
Br
(3) C CHCH CH(CH )2 23
Br
CH3
(a) 2 > 1 > 3 (b) 1 > 2 > 3(c) 2 > 3 > 1 (d) 1 > 3 > 2
44. Arrange the following three chlorides in decreas-ing order towards SN1 reactivity.
(1) Cl (2)Cl
(3)Cl
(a) 1 > 2 > 3 (b) 2 > 3 > 1(c) 2 > 1 > 3 (d) 3 > 2 > 1
45. Which of the following alkyl halide undergorearrangement in SN1 reaction?
(a) C CH
CH3
CH3CH3
CH3 I(b)
Cl
CH3
(c)
l
(d) All of these
46. Which of the following reactant will not favournucleophilic substitution reaction?
(a)Br
(b) Ph – Br
(c) C CH2
CH3
BrCH3
CH3
(d) All the above
47. Among the pairs, in which pair first compoundreacts faster then second compound in SN1 re-action?(a) CH3– CH2– CH2 – CH2 – Br or
CH2CH3
BrCH CH3
(b) CCH3
BrCH2 CH3
CH3
or CHCH3
BrCH CH3
CH3
Topper Package chemistry-XII Permutation and CombinationsAlkyl Halides & Aryl Halides
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(c)
HBr 3NaOCH
HOCH3
(d) Both (a) and (b)
51.CH C2–– lO
3 a
3 N
CH ONCH OH(S 1) Product
Which of the following products can be obtainedfrom above reaction?
(a)CH CH2–– O 3
O
(b) OCH3O
(c)O
OCH3
CH3
(d) All of these52. What is the principal product of the following re-
action?CH3
CH3
Cl
H
BrH
H
H + NaN3 Product
(a)
CH3
CH3
Cl
H
N3H
H
H (b)
CH3
CH3
H
H
HN3
H
Cl
(c)
CH3
CH3
Cl
H
HN3
H
H (d)
CH3
CH3
H
H
N3H
H
Cl
(c)
Br
or
Br
(d) CCH3
BrCH3
CH3
or CCH3
ICH3
CH3
48.
log
(rat
e)
CH – X3 Me– CH X2– Me CH – X2 Me C – X3
A SN²
SN1
B
Which of the following is true about given graphsA and B?
(a) A 1NS 2N
B S (b) A 2NS , 1N
B S
(c) 1A & B E (d) 2A & B E
49. In each of the following groups, which is thestrongest (best) nucleophile?
(I) (1) H3C – O– (2) O–
(3) H3 C – S– in CH3OH
(II) (1) OH– (2) H2O (3) NH –2 in DMF
(III) (1) O– (2) O– (3) CH3O– in DMSO
(a) I,3; II,3; III, 2 (b) I,1; II,1; III, 3(c)I, 1; II, 2;, III, 1 (d) I,3; II, 1; III, 3
50. Which of the following reaction is an elimina-tion reaction?
(a)
HOH 2 4H SO + H
(b)
H
Br
H
BrKI + IBr + KBr
Topper Package chemistry-XII Permutation and CombinationsAlkyl Halides & Aryl Halides
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(a) A reacts faster than B(b) B reacts faster than A(c) Both A and B reacts at the same rate(d) Neither A nor B reacts
58. Most reactive compound toward SN1
(a)
CH2 I
(b)
CH2 I
(b)
CH2 I
(d)
CH2 I
59.
C
CH
OH
23 2
32 4
1.NaNH (2eq.)__2.CH CH I
__3.CH I__4.H /Pd BaSO
Product (X) is:
(a)
CH CH2 3
CH 2 O CH3
(b)
OCH3
CH CH2 3
(c)
CH OCH CH2 2 3
CH3
(d)
O CH CH2 3
CH3
53. Which of the following is most reactive towardSN2 reaction?(a) CH2 = CH – CH2 – Cl(b) Ph – CH2 – Cl
(c) Me – O Cl(d)
O
Ph – C – CH – Cl2
54. 4-chloro-1-butanol + NaOH (B)Product (B) of the above reaction is:
(a)O
(b)O
(c)O
CH3
(d)
CH H2 3–C
O
55. Energy profile diagram for an exothermic reac-tion, 1 2 3A B C D , is given below:
The slowest rate of step of the reaction is:
(a) A B (b) B C
(c) C D (d) cannot predict
56. Me2C = CH – CH2 – CH2 – Cl 2
3
H OCaCO (X); Major
product of the reaction is:
(a) Me CMe
CH2 CH2 CH2
OH
(b) Me2C = CH – CH2 – CH2 – OH(c) Me C2 CH
OHCH CH2 OH
(d) CMe2
OH
57. Which of the following statements is correct re-garding the rate of hydrolysis of the compounds(A) and (B) by SN1 reaction ?
A
Br O
B
Br
Topper Package chemistry-XII Permutation and CombinationsAlkyl Halides & Aryl Halides
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60. The major product of the following reaction:
H
OH
HBr [ ]x
(a)
Br
H(b)
H
(c) HBr
(d) OHHTOPIC (3) PREPARATION & PHYSICAL
PROPERTIES OF ARYL HALIDE61. Chlorobenzene is
(a) less reactive than benzyl chloride(b) more reactive than ethyl bromide(c) nearly as reactive as methyl chloride(d) more reactive than isopropyl chloride
62. Westron is(a) vinyl chloride(b) allyl chloride(c) dichloroacetaldehyde(d) acetylene tetrachloride
63. Cl Heat Fe Br Zn HClC H A B C2 23 , / /7 8
Here, the compound C is(a) 3-Bromo, 2,4, 6-trichlorotoluene(b) o-bromotoluene(c) p-bromotoluene(d) m-bromotoluene
64. A solution of (+)-2chloro-2-phenylethane intoluene racemises slowly in the presence ofsmall amount of SbCl5 due to the formation of(a) Carbanion (b) Carbene(c) Free-radical (d) Carbocation
65.
CH2—CH3
O2NBr2. U.V. light
Br2/Fe(A)
(B)(A) & (B) are respectively
(a)
CH2CH3
O2NBr
and
CH2CH3
O2NBr
(b)
CH2CH3
O2NBr
and CH—CH3
O2N
Br
(c)
C2H5
O2NBr
and CH—CH3
O2N
Br
(d)CH—CH3
O2N
Br
and
CH2CH3
O2NBr
66. Consider the two reaction
(I)
(C6H )6
BrH
+ Br2FeBr3
(II)
D
D
DD
D
D
+ Br2FeBr3
(C D )6 6
Br
D
DD
D
D
Which is the correct statement ?(a) The rate of bromination is same in both the
cases(b) The rate of bromination in (I) is more than
in (II)(c) The rate of bromination in (II) is more than
in (I)(d) The rate of bromination in (I) is double than
in (II)
67. The compound ‘X’ in the following reaction is:
(a) (b)
(c) (d)
Topper Package chemistry-XII Permutation and CombinationsAlkyl Halides & Aryl Halides
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68. Toluene reacts with excess of Cl2 in presence ofsunlight to give a product which on hydrolysisfollowed by reaction with NaOH gives
(a)
COOH
Cl(b)
COOH
(c)
COONa
Na
(d) None of these
TOPIC (4) CHEMICAL PROPERTIES69. Aryl halides and Alkyl halides are distinguished
by(a) Alcoholic 3AgNO (b) Aq. 3AgNO(c) 3AgNO /ether (d) 3 3/AgNO NH
70. Silver benzoate will react with bromine inacetone to form
(a)
(b)
Br
(c)
COOAg
Br
(d)
O||C Br
71. The reaction of toluene with chlorine in thepresence of 3FeCl gives mainly(a) m-chlorobenzene(b) o- and p-chlor toluene(c) benzyl chloride(d) Benzoyl chloride
72. Which chloroderivative of benzene among thefollowing would undergo hydrolysis most readilywith aqueous sodium hydroxide to furnish thecorresponding hydroxyderivative?
(a)ClO N2
NO2
NO2
(b) ClO N2
(c) ClMe2N (d) C H6 5Cl
73. Which represents nucleophil ic aromaticsubstitution reaction?
(a) reaction of benzene with Cl2 in sunlight(b) benzyl bromide hydrolysis with water(c) reaction of NaOH with dinitrofluoro benzene(d) sulphonation of benzene.
74. Chlorination of toluene in presence of light andheat followed by treatment with aqueous NaOHand acidification gives(a) o-Cresol(b) p-Cresol(c) 2,4-Dihydroxytoluene(d) benzoic acid
75. The major product obtained when Br Fe2 / is
treated with HN
CH3
O
H C3 is
(a)
HNCH3
O
H C3
Br
(b)
HNCH3
O
H C3
Br
(c)
HNCH3
O
H C3
Br
(d)
HNCH3
O
H C3
Br
76. The decreasing order of reactivity towards OH
ions is(I) m-nitrobromobenzene(II) 2,4,6-trinitrobromobenzene(III) p-nitrobromobenzene(IV) 2,4-dinitro bromobenzene(a) I > II > III > IV (b) II > IV > III > I(c) IV > II > III > I (d) II > IV > I > III
Topper Package chemistry-XII Permutation and CombinationsAlkyl Halides & Aryl Halides
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77. o-Toluic acid on reaction with Br Fe2 gives
(a)
ClCO H2
(b)Br
CO H2
CH3
(c)
Br
CO H2
CH3
(d)Br
CO H2
CH3
78. In the reaction of p-chlorotoluene with KNH2 in
liq. NH3 , the major product is
(a) o-toluidine (b) m-toluidine(c) p-toluidine (d) p-chloroaniline
79. Which is not the Wurtz-Fittig reaction?
(a) CH2Cl + CH3Cl /Na ether
(b) CH2C +l Cl /Na ether
(c) Cl +CH C3 l /Na ether
(d) None of these
80.
H C3 CH3
Cl
CH3
FeCl3CH3NO , 0°C2
A ;
A is
(a)
CH3
CH3
CH3
(b)
CH2CH3
CH3H C3
(c) both are correct(d) none is correct
81. Cl
Cl
C
H
CCl3
The above structural formula refers to :(a) BHC (b) DNA(c) DDT (d) RNA
82. Which of the following is most reactive towardsSN2 reaction ?
(a)
CH3
Cl
(b)
Cl
(c)
Cl
Cl
(d)
NO2
Cl
83. (CH ) – CH – Cl22S
O
O4
2NaNHdimethoxy ethane (A);Product(A) is:
(a) (CH ) –CH CH2 3 2S
O
O
(b) S
O
O
(c) (CH ) –CH NH2 4 2 2S
O
O(d) None of these
Topper Package chemistry-XII Permutation and CombinationsAlkyl Halides & Aryl Halides
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84.
CH3
NBS
Major(A) Major product is (A) is:
(a)
Br
(b)
Br
(c)
Br
(d)Br
85.
CH3
Br2 2SO Cl NBS KSHhv (A) (B) (C) ,
Product (C) is:
(a)
SH
Br (b)
SH
Cl
(c)
Br
SH (d)
Br
86. C
CH3
C14 CH3CH3
H
OTs
Major product of the
reaction is:
(a)CH3
CH3
C14
CPh
CH3
(b) HC3 CCH3
CH
Ph
CH2
14
(c)CH3
CH3
C14C
Ph
CH3
(d)
CH3
CH3
C
14
CPh
CH3
87.Br
H H
CH3
+ OH– 2SNA; The product A
is:
(a)HO
H H
CH3
(b)HO
H
H
CH3
(c) Both (a) and (b) are correct(d) None is correct
88.
OH
CH OH2
HBrΔ (A),
OH
OCH3
HBrΔ (B)
Product (A) and (B) respectively are:
(a)
OH
CH Br2
and
OH
Br
(b)
OH
CH Br2
and
OH
OH
(c)
OHHO
CH3
and
Br
OCH3
(d)
Br
CH OH2
and
Br
OCH3
Topper Package chemistry-XII Permutation and CombinationsAlkyl Halides & Aryl Halides
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INTEGER TYPE QUESTION
1 . CH C C CH3 3
Br Br
Br Br
(a) NaNH2
(b) CH I3
CH C C C C CH3 3
a and b mole consumed.Value of a + b =
2 . a.
Br
alc. KOH (A) products
b.
Br
alc. KOH (B)
c. Br
alc. KOH (C)
d.
CH3
CH3
BrBr
H
alc. KOH (D)
Sum of A + B + C + D =3.
a.
OH
H
(A)
b. OH
H
(B)
c.
OH
H
(C)
d . OH
H
(D)
Total number of product obtained in above re-actions including minor product is (includ-ing stereoisomer)
4 .
Cl
ClCl
Cl
(a ) alC.KOH
Moles of alc. KOH consumed are:
5 .
CH OH2
OH (A) HBr ; Value of (A)
is:
6 . Ph CH CH 2
Br
Br
(X) NaNH2
Ph C C Na+–
(X = No. of moles of NaNH2)
7 .O
a PCl5 b NaNH2
CH I3
C C CH3
Cl
Sum of a + b =
8 .
Cl
CH3
CH OH3 ?
X = Total number of substitution and elimi-nation product (s). Find the value of X.
9 . 1, 2-Dibromopropane on treatment with Xmoles of NaNH2 followed by treatment withC2H5Br gives a pentyne. The value of X is :
Topper Package chemistry-XII Permutation and CombinationsAlkyl Halides & Aryl Halides
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ANSWER’SUNIT : 7. ALKYL, ARYL & HALIDE
1. b 2. b 3. b 4. d 5. b6. a 7. b 8. c 9. d 10. a11. b 12. b 13. a 14. b 15. c16. a 17. d 18. d 19. d 20. d21. d 22. c 23. c 24. c 25. b26. b 27. b 28. a 29. d 30. d31. d 32. c 33. c 34. d 35. a36. a 37. b 38. d 39. c 40. c41. b 42. b 43. c 44. b 45. d46. d 47. b 48. b 49. d 50. d51. d 52. c 53. d 54. b 55. a56. d 57. b 58. d 59. b 60. c61. a 62. d 63. d 64. d 65. b66. a 67. b 68. b 69. a 70. b71. b 72. a 73. c 74. d 75. a76. b 77. c 78. b 79. a 80. b81. c 82. d 83. b 84. a 85. b86. c 87. b 88. b
INTEGER QUESTIONS1. 8 2. 8 3. 9 4. 2 5. 16. 3 7. 5 8. 4 9. 3