Chemical Bonding Online test as a assignmnet | Additional Documents & Tests for IIT JAM PDF Download

 Page 1


 
2637, Hudson Lane, Behind Khalsa College, Near G.T.B. Nagar Metro Station Gate No. 3 & 4, New Delhi – 110009 
Mob. 011-47455430, 08860929430, e-mail: info@asfinstitute.com, www.asfinstitute.com 
Chemical Bonding & Solid State Online Test (26
th
, Dec/16) 
1. The number of peroxide linkages and oxidation state of Cr in CrO
5
: 
 (a) 2, +6  (b) 1, +6  (c) 1, +8  (d) 2, +8 
2. The correct structure of [P(C
3
H
5
)
2
(CH
3
)
3
] is: 
 (a)    (b) 
CH
3
CH
3
H
3
C P
 
 (c)    (d) 
 
3. Increasing order of bond angle of: 
 (a) Cl
2
O < ClO
2
 < Cl
2
O
7
 < I
3
-
   (b) Cl
2
O < ClO
2
 < I
3
-
 < Cl
2
O
7
  
 (c) I
-
3
 < Cl
2
O
7
 < ClO
2
 < Cl
2
O   (d) Cl
2
O <  Cl
2
O
7 
< ClO
2
 < I
3
- 
4. Which of the following species are all the bonds not equal: 
 (a) SF
4
   (b) SiF
4
  (c) XeF
4
  (d) BF
4
- 
5. Which of the following species has two non-bonded electron pairs on the central atom: 
 (a) TeCl
4
  (b) ClF
3
  (c) ICl
2
   (d) PCl
3
  
6. In the MO configuration of XeF
2
, how many pairs are present in BMO, NBO, ABMO, 
respectively: 
 (a) 2, 0, 2  (b) 2, 1, 1  (c) 2, 2, 0  (d) 1, 2, 1 
7. In which of following C-C bond length will be longest: 
 (a) CH
3
–CF
3
  (b) FCH
2
–CH
2
F (c) F
2
CH–CHF
2
 (d) CF
3
–CF
3 
8. The correct order of bond strength: 
 (I) H–F > H–H > F–F    (II) N–N < P–P  
 (III) As–F > P–F > N–F   (IV) P–O > As–O > N–O 
 (a) I, II, III  (b) II, III, IV  (c) I, III, IV  (d) I, II, IV 
9. The probable state of hybridization for the transition state of hydrolysis mechanism of BCl
3
 and 
SF
4
 respectively: 
 (a) sp
2
, sp
3
d  (b) sp
3
, sp
3
  (c) sp
3
, sp
3
d
2  
(d) sp
3
, sp
3
d 
Page 2


 
2637, Hudson Lane, Behind Khalsa College, Near G.T.B. Nagar Metro Station Gate No. 3 & 4, New Delhi – 110009 
Mob. 011-47455430, 08860929430, e-mail: info@asfinstitute.com, www.asfinstitute.com 
Chemical Bonding & Solid State Online Test (26
th
, Dec/16) 
1. The number of peroxide linkages and oxidation state of Cr in CrO
5
: 
 (a) 2, +6  (b) 1, +6  (c) 1, +8  (d) 2, +8 
2. The correct structure of [P(C
3
H
5
)
2
(CH
3
)
3
] is: 
 (a)    (b) 
CH
3
CH
3
H
3
C P
 
 (c)    (d) 
 
3. Increasing order of bond angle of: 
 (a) Cl
2
O < ClO
2
 < Cl
2
O
7
 < I
3
-
   (b) Cl
2
O < ClO
2
 < I
3
-
 < Cl
2
O
7
  
 (c) I
-
3
 < Cl
2
O
7
 < ClO
2
 < Cl
2
O   (d) Cl
2
O <  Cl
2
O
7 
< ClO
2
 < I
3
- 
4. Which of the following species are all the bonds not equal: 
 (a) SF
4
   (b) SiF
4
  (c) XeF
4
  (d) BF
4
- 
5. Which of the following species has two non-bonded electron pairs on the central atom: 
 (a) TeCl
4
  (b) ClF
3
  (c) ICl
2
   (d) PCl
3
  
6. In the MO configuration of XeF
2
, how many pairs are present in BMO, NBO, ABMO, 
respectively: 
 (a) 2, 0, 2  (b) 2, 1, 1  (c) 2, 2, 0  (d) 1, 2, 1 
7. In which of following C-C bond length will be longest: 
 (a) CH
3
–CF
3
  (b) FCH
2
–CH
2
F (c) F
2
CH–CHF
2
 (d) CF
3
–CF
3 
8. The correct order of bond strength: 
 (I) H–F > H–H > F–F    (II) N–N < P–P  
 (III) As–F > P–F > N–F   (IV) P–O > As–O > N–O 
 (a) I, II, III  (b) II, III, IV  (c) I, III, IV  (d) I, II, IV 
9. The probable state of hybridization for the transition state of hydrolysis mechanism of BCl
3
 and 
SF
4
 respectively: 
 (a) sp
2
, sp
3
d  (b) sp
3
, sp
3
  (c) sp
3
, sp
3
d
2  
(d) sp
3
, sp
3
d 
 
2637, Hudson Lane, Behind Khalsa College, Near G.T.B. Nagar Metro Station Gate No. 3 & 4, New Delhi – 110009 
Mob. 011-47455430, 08860929430, e-mail: info@asfinstitute.com, www.asfinstitute.com 
10. Band theory predicts that magnesium is an insulator. However, in practice it act as a conductor 
due to: 
 (a) Presence of filled 3s-orbital   (b) Overlap of filled 2p and filled 3s-orbital. 
 (c) Overlap of filled 3s and empty 3p-orbital.(d) Pressure of unfilled 3p-orbital. 
11. The number of nodal plane in p antibonding molecular orbital of acetylene: 
 (a) 2   (b) 1   (c) 0   (d) 3  
12. The shape and hybridization of KrF
2
 is: 
 (a) Trigonal bipyramidal ; sp
3
d  (b) Square pyramidal ; dsp
3
 
 (c) Linear ; sp
3
d    (d) Linear ; sp
2
d 
13. Number of second neighbours atom in SC, BCC & FCC respectively are: 
 (a) 6, 8, 12  (b) 12, 6, 6  (c) 6, 6, 12  (d) 6, 12, 6   
14. The bond order for N
2
, O
2
, N
2
–
, O
2
–
 varies as: 
 (a) N
2
 > N
2
–
 > O
2
 > O
2
–
   (b) N
2
 > O
2
 > N
2
–
 > O
2
–
 
 (c) O
2
 > N
2
 > O
2
–
 > N
2
–
   (d) N
2
–
 > N
2
 > O
2
–
 > O
2
 
15. Iron (II) Oxide, FeO, crystal has a cubic structure and each edge of the number cell is 5.0 Å. 
Density of the oxide is 4.0 g cm
–3
. Number of Fe
2+
 and O
2–
 ions present in each cell will be: 
 (a) One Fe
2+
 ions and one O
2–
 ions.  (b) Two Fe
2+
 ions and two O
2–
 ions. 
 (c) Three Fe
2+
 ions and three O
2–
 ions. (d) Four Fe
2+
 ions and four O
2–
 ions. 
16. Which one of the following statements is correct: 
 (a) Frenkel defect is a cation vacancy and a cation interstitial. 
 (b) Frenkel defect is anion vacancy and a cation interstitial. 
 (c) Density of solid remains unchanged in case of Frenkel defects. 
 (d) Density of a solid decrease in case of  Schottky defects. 
17. The incorrect statement among the following is: 
 (a) N
2
 has higher bond order than N
2
+
 has hence has larger bond length compared to N
2
+
. 
 (b) N
2
+
 has higher bond order than N
2
 and has larger bond length compared to N
2
. 
(c) N
2
 has higher bond order than N
2
+
 and hence has higher dissociation energy compared to N
2
+
. 
(d) N
2
 has lower bond order than N
2
+
 and hence has lower dissociation energy compared to N
2
+
 
energy. 
18. In which one of the following pairs, molecules have different shape: 
 (a) 
5 5
SiF and PCl
?
 (b) 
4 4
ICl and XeF
?
 (c) 
2
4 4
SO and SF
?
 (d) 
4 4
AsF and XeF
?
 
Page 3


 
2637, Hudson Lane, Behind Khalsa College, Near G.T.B. Nagar Metro Station Gate No. 3 & 4, New Delhi – 110009 
Mob. 011-47455430, 08860929430, e-mail: info@asfinstitute.com, www.asfinstitute.com 
Chemical Bonding & Solid State Online Test (26
th
, Dec/16) 
1. The number of peroxide linkages and oxidation state of Cr in CrO
5
: 
 (a) 2, +6  (b) 1, +6  (c) 1, +8  (d) 2, +8 
2. The correct structure of [P(C
3
H
5
)
2
(CH
3
)
3
] is: 
 (a)    (b) 
CH
3
CH
3
H
3
C P
 
 (c)    (d) 
 
3. Increasing order of bond angle of: 
 (a) Cl
2
O < ClO
2
 < Cl
2
O
7
 < I
3
-
   (b) Cl
2
O < ClO
2
 < I
3
-
 < Cl
2
O
7
  
 (c) I
-
3
 < Cl
2
O
7
 < ClO
2
 < Cl
2
O   (d) Cl
2
O <  Cl
2
O
7 
< ClO
2
 < I
3
- 
4. Which of the following species are all the bonds not equal: 
 (a) SF
4
   (b) SiF
4
  (c) XeF
4
  (d) BF
4
- 
5. Which of the following species has two non-bonded electron pairs on the central atom: 
 (a) TeCl
4
  (b) ClF
3
  (c) ICl
2
   (d) PCl
3
  
6. In the MO configuration of XeF
2
, how many pairs are present in BMO, NBO, ABMO, 
respectively: 
 (a) 2, 0, 2  (b) 2, 1, 1  (c) 2, 2, 0  (d) 1, 2, 1 
7. In which of following C-C bond length will be longest: 
 (a) CH
3
–CF
3
  (b) FCH
2
–CH
2
F (c) F
2
CH–CHF
2
 (d) CF
3
–CF
3 
8. The correct order of bond strength: 
 (I) H–F > H–H > F–F    (II) N–N < P–P  
 (III) As–F > P–F > N–F   (IV) P–O > As–O > N–O 
 (a) I, II, III  (b) II, III, IV  (c) I, III, IV  (d) I, II, IV 
9. The probable state of hybridization for the transition state of hydrolysis mechanism of BCl
3
 and 
SF
4
 respectively: 
 (a) sp
2
, sp
3
d  (b) sp
3
, sp
3
  (c) sp
3
, sp
3
d
2  
(d) sp
3
, sp
3
d 
 
2637, Hudson Lane, Behind Khalsa College, Near G.T.B. Nagar Metro Station Gate No. 3 & 4, New Delhi – 110009 
Mob. 011-47455430, 08860929430, e-mail: info@asfinstitute.com, www.asfinstitute.com 
10. Band theory predicts that magnesium is an insulator. However, in practice it act as a conductor 
due to: 
 (a) Presence of filled 3s-orbital   (b) Overlap of filled 2p and filled 3s-orbital. 
 (c) Overlap of filled 3s and empty 3p-orbital.(d) Pressure of unfilled 3p-orbital. 
11. The number of nodal plane in p antibonding molecular orbital of acetylene: 
 (a) 2   (b) 1   (c) 0   (d) 3  
12. The shape and hybridization of KrF
2
 is: 
 (a) Trigonal bipyramidal ; sp
3
d  (b) Square pyramidal ; dsp
3
 
 (c) Linear ; sp
3
d    (d) Linear ; sp
2
d 
13. Number of second neighbours atom in SC, BCC & FCC respectively are: 
 (a) 6, 8, 12  (b) 12, 6, 6  (c) 6, 6, 12  (d) 6, 12, 6   
14. The bond order for N
2
, O
2
, N
2
–
, O
2
–
 varies as: 
 (a) N
2
 > N
2
–
 > O
2
 > O
2
–
   (b) N
2
 > O
2
 > N
2
–
 > O
2
–
 
 (c) O
2
 > N
2
 > O
2
–
 > N
2
–
   (d) N
2
–
 > N
2
 > O
2
–
 > O
2
 
15. Iron (II) Oxide, FeO, crystal has a cubic structure and each edge of the number cell is 5.0 Å. 
Density of the oxide is 4.0 g cm
–3
. Number of Fe
2+
 and O
2–
 ions present in each cell will be: 
 (a) One Fe
2+
 ions and one O
2–
 ions.  (b) Two Fe
2+
 ions and two O
2–
 ions. 
 (c) Three Fe
2+
 ions and three O
2–
 ions. (d) Four Fe
2+
 ions and four O
2–
 ions. 
16. Which one of the following statements is correct: 
 (a) Frenkel defect is a cation vacancy and a cation interstitial. 
 (b) Frenkel defect is anion vacancy and a cation interstitial. 
 (c) Density of solid remains unchanged in case of Frenkel defects. 
 (d) Density of a solid decrease in case of  Schottky defects. 
17. The incorrect statement among the following is: 
 (a) N
2
 has higher bond order than N
2
+
 has hence has larger bond length compared to N
2
+
. 
 (b) N
2
+
 has higher bond order than N
2
 and has larger bond length compared to N
2
. 
(c) N
2
 has higher bond order than N
2
+
 and hence has higher dissociation energy compared to N
2
+
. 
(d) N
2
 has lower bond order than N
2
+
 and hence has lower dissociation energy compared to N
2
+
 
energy. 
18. In which one of the following pairs, molecules have different shape: 
 (a) 
5 5
SiF and PCl
?
 (b) 
4 4
ICl and XeF
?
 (c) 
2
4 4
SO and SF
?
 (d) 
4 4
AsF and XeF
?
 
 
2637, Hudson Lane, Behind Khalsa College, Near G.T.B. Nagar Metro Station Gate No. 3 & 4, New Delhi – 110009 
Mob. 011-47455430, 08860929430, e-mail: info@asfinstitute.com, www.asfinstitute.com 
19. The number of lone pair are different in the pair: 
 (a) 
4 3
XeF ;ClF  (b) 
4 4
XeO ;ICl
?
 (c) 
2 2 4
XeO F ;ICl
?
 (d) 
4 3
XeO ;ClF  
20. Which of the following statement (s) is/are correct: 
 (a) Bond – length of CO
+
 is shorter than CO.  
 (b) Bond – length of CO
+
 is longer than CO. 
 (c) Both CO
+
 and CO has equal bond length. 
 (d) Bond order of CO
+
 is greater than CO.   
21. The number of fully planar molecules among I
3
+
. I
3
–
, H
2
O, NH
2
–
, I(CN)
2
–
, I
2
Cl
6
 
22. The bond length in O
2
 is 121 pm. The number of species having longer bond length than 121 pm: 
 O
2
-
, O
2
+
, H
2
O
2
, O
2
F
2
, O
2
2– 
23. The coordination number of the Ba
2+
 ions in barium fluoride is 8. The coordination number of the 
fluoride is: 
24. Among SF
4
, ClO
2
, XeF
4
 and ICl
4
–
 the number of species having two lone pair of electrons on the 
central atom according to VSEPR theory is: 
25. For a simple cubic crystal, X-ray diffraction shows intense reflections for angles ?
1
 and ?
2
 which 
are assigned to [101] and [111] planes, respectively, the ratio sin ?
1
/sin ?
2
 is: 
26. The no. of paramegnetic species among -triplate carbene, O
2, 
ClO
2
, NO
2
, N
2
O, methyl radical 
anion: 
27. A newly synthesized copper complex with molecular formula C
11
H
29
N
5
B
2
Cu is found to 
crystallize in the orthorhombic system with a = 14.709 Å, b = 17.604 Å and c = 13.907 Å. The 
density is 1.17 g cm
–3
. Number of molecular per unit cell with be (B = 11, Cu = 63.5) 
28. The angle at which the first order braggs reflection is observed from (110) plane in a simple cubic 
unit cell of side 3.238 Å, when chromium k
?
 radiation of wavelength 2.29 Å is used is:(in degree)  
29. The minimum number of electrons needed to form a chemical bond between two atom is: 
30. An element crystallizes in fcc lattice having edge length 400 pm. Calculate the maximum 
diameter of atom which can be placed in interstitial site without distorting the structure: (in pm) 
 
 
 
Page 4


 
2637, Hudson Lane, Behind Khalsa College, Near G.T.B. Nagar Metro Station Gate No. 3 & 4, New Delhi – 110009 
Mob. 011-47455430, 08860929430, e-mail: info@asfinstitute.com, www.asfinstitute.com 
Chemical Bonding & Solid State Online Test (26
th
, Dec/16) 
1. The number of peroxide linkages and oxidation state of Cr in CrO
5
: 
 (a) 2, +6  (b) 1, +6  (c) 1, +8  (d) 2, +8 
2. The correct structure of [P(C
3
H
5
)
2
(CH
3
)
3
] is: 
 (a)    (b) 
CH
3
CH
3
H
3
C P
 
 (c)    (d) 
 
3. Increasing order of bond angle of: 
 (a) Cl
2
O < ClO
2
 < Cl
2
O
7
 < I
3
-
   (b) Cl
2
O < ClO
2
 < I
3
-
 < Cl
2
O
7
  
 (c) I
-
3
 < Cl
2
O
7
 < ClO
2
 < Cl
2
O   (d) Cl
2
O <  Cl
2
O
7 
< ClO
2
 < I
3
- 
4. Which of the following species are all the bonds not equal: 
 (a) SF
4
   (b) SiF
4
  (c) XeF
4
  (d) BF
4
- 
5. Which of the following species has two non-bonded electron pairs on the central atom: 
 (a) TeCl
4
  (b) ClF
3
  (c) ICl
2
   (d) PCl
3
  
6. In the MO configuration of XeF
2
, how many pairs are present in BMO, NBO, ABMO, 
respectively: 
 (a) 2, 0, 2  (b) 2, 1, 1  (c) 2, 2, 0  (d) 1, 2, 1 
7. In which of following C-C bond length will be longest: 
 (a) CH
3
–CF
3
  (b) FCH
2
–CH
2
F (c) F
2
CH–CHF
2
 (d) CF
3
–CF
3 
8. The correct order of bond strength: 
 (I) H–F > H–H > F–F    (II) N–N < P–P  
 (III) As–F > P–F > N–F   (IV) P–O > As–O > N–O 
 (a) I, II, III  (b) II, III, IV  (c) I, III, IV  (d) I, II, IV 
9. The probable state of hybridization for the transition state of hydrolysis mechanism of BCl
3
 and 
SF
4
 respectively: 
 (a) sp
2
, sp
3
d  (b) sp
3
, sp
3
  (c) sp
3
, sp
3
d
2  
(d) sp
3
, sp
3
d 
 
2637, Hudson Lane, Behind Khalsa College, Near G.T.B. Nagar Metro Station Gate No. 3 & 4, New Delhi – 110009 
Mob. 011-47455430, 08860929430, e-mail: info@asfinstitute.com, www.asfinstitute.com 
10. Band theory predicts that magnesium is an insulator. However, in practice it act as a conductor 
due to: 
 (a) Presence of filled 3s-orbital   (b) Overlap of filled 2p and filled 3s-orbital. 
 (c) Overlap of filled 3s and empty 3p-orbital.(d) Pressure of unfilled 3p-orbital. 
11. The number of nodal plane in p antibonding molecular orbital of acetylene: 
 (a) 2   (b) 1   (c) 0   (d) 3  
12. The shape and hybridization of KrF
2
 is: 
 (a) Trigonal bipyramidal ; sp
3
d  (b) Square pyramidal ; dsp
3
 
 (c) Linear ; sp
3
d    (d) Linear ; sp
2
d 
13. Number of second neighbours atom in SC, BCC & FCC respectively are: 
 (a) 6, 8, 12  (b) 12, 6, 6  (c) 6, 6, 12  (d) 6, 12, 6   
14. The bond order for N
2
, O
2
, N
2
–
, O
2
–
 varies as: 
 (a) N
2
 > N
2
–
 > O
2
 > O
2
–
   (b) N
2
 > O
2
 > N
2
–
 > O
2
–
 
 (c) O
2
 > N
2
 > O
2
–
 > N
2
–
   (d) N
2
–
 > N
2
 > O
2
–
 > O
2
 
15. Iron (II) Oxide, FeO, crystal has a cubic structure and each edge of the number cell is 5.0 Å. 
Density of the oxide is 4.0 g cm
–3
. Number of Fe
2+
 and O
2–
 ions present in each cell will be: 
 (a) One Fe
2+
 ions and one O
2–
 ions.  (b) Two Fe
2+
 ions and two O
2–
 ions. 
 (c) Three Fe
2+
 ions and three O
2–
 ions. (d) Four Fe
2+
 ions and four O
2–
 ions. 
16. Which one of the following statements is correct: 
 (a) Frenkel defect is a cation vacancy and a cation interstitial. 
 (b) Frenkel defect is anion vacancy and a cation interstitial. 
 (c) Density of solid remains unchanged in case of Frenkel defects. 
 (d) Density of a solid decrease in case of  Schottky defects. 
17. The incorrect statement among the following is: 
 (a) N
2
 has higher bond order than N
2
+
 has hence has larger bond length compared to N
2
+
. 
 (b) N
2
+
 has higher bond order than N
2
 and has larger bond length compared to N
2
. 
(c) N
2
 has higher bond order than N
2
+
 and hence has higher dissociation energy compared to N
2
+
. 
(d) N
2
 has lower bond order than N
2
+
 and hence has lower dissociation energy compared to N
2
+
 
energy. 
18. In which one of the following pairs, molecules have different shape: 
 (a) 
5 5
SiF and PCl
?
 (b) 
4 4
ICl and XeF
?
 (c) 
2
4 4
SO and SF
?
 (d) 
4 4
AsF and XeF
?
 
 
2637, Hudson Lane, Behind Khalsa College, Near G.T.B. Nagar Metro Station Gate No. 3 & 4, New Delhi – 110009 
Mob. 011-47455430, 08860929430, e-mail: info@asfinstitute.com, www.asfinstitute.com 
19. The number of lone pair are different in the pair: 
 (a) 
4 3
XeF ;ClF  (b) 
4 4
XeO ;ICl
?
 (c) 
2 2 4
XeO F ;ICl
?
 (d) 
4 3
XeO ;ClF  
20. Which of the following statement (s) is/are correct: 
 (a) Bond – length of CO
+
 is shorter than CO.  
 (b) Bond – length of CO
+
 is longer than CO. 
 (c) Both CO
+
 and CO has equal bond length. 
 (d) Bond order of CO
+
 is greater than CO.   
21. The number of fully planar molecules among I
3
+
. I
3
–
, H
2
O, NH
2
–
, I(CN)
2
–
, I
2
Cl
6
 
22. The bond length in O
2
 is 121 pm. The number of species having longer bond length than 121 pm: 
 O
2
-
, O
2
+
, H
2
O
2
, O
2
F
2
, O
2
2– 
23. The coordination number of the Ba
2+
 ions in barium fluoride is 8. The coordination number of the 
fluoride is: 
24. Among SF
4
, ClO
2
, XeF
4
 and ICl
4
–
 the number of species having two lone pair of electrons on the 
central atom according to VSEPR theory is: 
25. For a simple cubic crystal, X-ray diffraction shows intense reflections for angles ?
1
 and ?
2
 which 
are assigned to [101] and [111] planes, respectively, the ratio sin ?
1
/sin ?
2
 is: 
26. The no. of paramegnetic species among -triplate carbene, O
2, 
ClO
2
, NO
2
, N
2
O, methyl radical 
anion: 
27. A newly synthesized copper complex with molecular formula C
11
H
29
N
5
B
2
Cu is found to 
crystallize in the orthorhombic system with a = 14.709 Å, b = 17.604 Å and c = 13.907 Å. The 
density is 1.17 g cm
–3
. Number of molecular per unit cell with be (B = 11, Cu = 63.5) 
28. The angle at which the first order braggs reflection is observed from (110) plane in a simple cubic 
unit cell of side 3.238 Å, when chromium k
?
 radiation of wavelength 2.29 Å is used is:(in degree)  
29. The minimum number of electrons needed to form a chemical bond between two atom is: 
30. An element crystallizes in fcc lattice having edge length 400 pm. Calculate the maximum 
diameter of atom which can be placed in interstitial site without distorting the structure: (in pm) 
 
 
 
 
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Answer key 
1.  (a) 2.  (b) 3.  (d) 4.  (a) 5.  (b) 
6.  (c) 7.  (b) 8.  (d) 9.  (c) 10.  (c) 
11.  (a) 12.  (c) 13.  (b) 14.  (a) 15.  (d) 
16.  (a,c,d) 17.  (a,b,d) 18.  (c,d) 19.  (b,c,d) 20.  (a,d) 
21.  (6) 22.  (4) 23.  (4) 24.  (2) 25.  (0.80 - 
0.84) 
26.  (5) 27.  (8 – 9) 28.  (30) 29.  (1) 30.  (115 – 
119)