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ICH602S - INORGANIC CHEMISTRY - 2ND OPP - JANUARY 2025 |
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nAmlBIA UnlVERSITY
OF SCtEnCE AnDTECHnOLOGY
Facultyof Health, Natural
ResourcesandApplied
Sciences
School of Natural and Applied
Sciences
Department of Biology,
Chemistry and Physics
QUALIFICATION : BACHELOR OF SCIENCE
QUALIFICATION CODE: 07BOSC
COURSE:INORGANIC CHEMISTRY
DATE: JANUARY 2025
DURATION: 3 HOURS
13Jackson Kaujeua Street
Private Bag 13388
Windhoek
NAMIBIA
T: •264 61 207 2012
F: •26d 61207 9012
E: dbcp@nust.na
W: www.nust.na
LEVEL:6
COURSECODE: ICH602S
SESSION: 1
MARKS: 100
SECOND OPPORTUNITY: QUESTION PAPER
.I
EXAMINER:
Dr Euodia Hess
MODERATOR:
Prof Habauka Kwaambwa
INSTRUCTIONS
1. Answer all questions on the separate answer sheet.
2. Please write neatly and legibly.
3. Do not use the left side margin of the exam paper. This must be allowed for the
examiner.
4. No books, notes and other additional aids are allowed.
5. Mark all answers clearly with their respective question numbers.
PERMISSIBLE MATERIALS:
1. Non-Programmable Calculator
ATTACHMENTS
1. List of useful constants
2. Periodic Table
This paper consists of 7 pages including this front page
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SECTION A: MULTIPLE CHOICE
[40 MARKS]
QUESTION 1:
There are 20 multiple choice questions in this section. Each question carries 2 marks.
1. What is the maximum oxidation state expected for manganese?
A. +7
B. +6
C. +5
D. +8
2. Which of the following salts would not be expected to have unpaired d-electrons?
A. CdCb
B. NiCb
C. MnCb
D. CoCl2
3. Ions such as [Co(H2O}GJ3+and [Ag(CN}zt are called __ .
A. Ligands
B. Coordination complexes
C. Chelates
D. Lewis bases
4. What is the oxidation state of molybdenum in [Mo(H2O)sOH]Cb?
A. +2
B. +3
C. +6
D. +5
5. What is the coordination number of the transition metal ion in [Ni(NH 3)6]CI?
A. 4
B. 6
C. 3
D. i
6. What is the hybridization of the central atom in a molecule with a tetrahedral molecular
geometry?
A. sp2
B. sp
C. sp3
D. sp3d
7. What is the hybridization of each carbon atom in benzene, CGHG?
A. sp
B. sp2
C. sp3
D. sp4
8. For which of the following molecules does the carbon atom have sp3hybridization?
A. CbCO
B. CO
C. CS2
D. CH2Cb
Inorganic Chemistry (ICH602S)
2nd Opportunity January 2025
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9. What is the molecular geometry around a central atom that is sp 2 hybridized, has three
sigma bonds, and one pi bond?
A. trigonal-planar
B. trigonal-pyramidal
C. square planar
D. T-shaped
10. Which of the following concerning o and 11 bonds is/are correct?
A. Pi bonds are formed from unhybridized p orbitals
B. Both A and D
C. Sigma bonds may only be formed from unhybridized orbitals Pi bonds are formed from
unhybridized p orbitals
D. A pi bond has an electron distribution above and below the bond axis
11. A molecular orbital that decreases the electron density between two nuclei is said to be
A. Hybridized
B. Bonding
C. pi-bonding
D. antibonding
12. The following valence molecular orbital energy level diagram is appropriate for which one of
the listed species?
0*2p
11*2p
1'
02p
1'.J,,
TT2p
1'.J,,
0*2s
1'.J,,
02s
1'.J,,
1'
1'.J,,
A. F2 2+
B. cz2+
C. Brz2+
D. Nz2+
13. Which molecule will have the following valence molecular orbital energy level diagram?
0*2p
11*2p
02p
J12p
0*2s
02s
A. B2
B. Be2
C. N2
D. 02
1'.J,,
1'.J,,
Inorganic Chemistry (ICH602S)
2nd Opportunity January 2025
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14. Which molecule will have the following valence molecular orbital level energy diagram?
0*2p
n:*2p
02p
1'~
IT2p
1'~
1'~
0*2s
1'~
02s
1'~
A. N2
B. C2
C. 02
D. 82
15. Which of the following correctly describes the states of matter and intermolecular forces?
A. The change in volume that accompanies the conversion of a liquid to a gas can be very
large.
B. The change in volume that accompanies the conversion of a liquid to a solid is small.
C. The forces of attraction between molecules in the liquid and solid state correlate with
melting point, boiling point, and the energy of phase changes.
D. All of the above
16. Which one of the following molecules will exhibit dipole-dipole intermolecular forces as a
pure liquid or solid?
A. C52
B. C2H2
C. 5iCl4
D. NH3
17. Which of the following bonds can potentially contribute to the formation of a hydrogen
bond in a solid or liquid?
A. Ge-H
B. 5i-H
C. 1-H
D. N-H
18. Hydrogen bonding is present in all of the following molecular solids EXCEPT__ .
A. H2504
B. CH3QH
C. HF
D. CH30CH3
19. As pure molecular solids, which of the following exhibit only induced dipole/induced dipole
forces: CO2,CH2Cli,and 502?
A. CO2only
B. CH2Clionly
C. CO2and CH2Cb
D. 502 only
20. What intermolecular force or bond is primarily responsible for the solubility of carbon
monoxide (CO) in water?
A. dipole/induced dipole force
B. dipole-dipole force
C. hydrogen bonding
D. ion-induced dipole force
Inorganic Chemistry (ICH6025)
2nd Opportunity January 2025
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SECTION B: SHORT/LONG ANSWER QUESTIONS
(60 MARKS)
There are THREE questions in this section. Please answer ALL of the questions in this section.
Show clearly, where necessary, how you arrive at the answer as all working will carry marks.
QUESTION 2:
2.1 Give the electron count of the following complexes and state whether they obey the
18-electron rule or not.
a) [Ni(ri 3-(3Hs)z]
b) [Co(ri3-C3Hs)(CO)z]
2.2 What are the names of the following organometallic complexes?
a) Rh(Me)(tO)z(PPh3)]
b) [V(CO)5]
2.3 Name each of the following compounds and give their electron count.
a) [Fe(CO)s]
b) [Mn2(CO)io
c) [V(CO)5]
d) [Fe(CO)4]2-
e) Rh(Me)(CO)z(PPh3)]
[20)
(6)
(4)
(10)
QUESTION 3:
[20)
3.1 Write the systematic names of the following coordination compounds
(6)
a) NaAuF4
b) K3(Fe(CN)5]
c) [Cr(en)3]C'3
3.2 What are the geometries of the following two complexes
(4)
a) [AICl4J-
b) [Ag(NH3)zj+
3.3 Write the formula of each of the following coordination compounds
(10)
a) Tetraammineplatinum(II) chloride
b) Sodium hexacyanoferrate(III)
c) Tris(ethylenediamine)platinum(IV) sulfate
d) Diamminesilver(I) nitrate
e) Potassium diaquadioxalatocobaltate(III)
QUESTION 4:
[20)
4.1 Draw the Molecular Orbital (MO) energy diagram for the following molecules and calculate their
bond orders.
a) He2
(5)
b) C2
(5)
4.2 Arrange the following in order of increasing stability by using MO energy diagram and writing
their respective electron configuration.
(10)
Lh; Lh+; Liz"
END OF QUESTION PAPER
Inorganic Chemistry (ICH602S)
2nd Opportunity January 2025
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LIST OF USEFUL CONSTANTS:
Gas constant, R = 8.3145 J · moI-1 · K-1 = 0.083145 dm 3 ·bar· moI-1 · K-1 = 0.08206 L atm moI-1 · K·1
1 Pa· m3 = 1 kPa.L = 1 N ·m = 1 J
1 atm = 101 325 Pa= 760 mm Hg= 760 torr
Avogadro's Number, NA= 6.022 x 1023 moI·1
Planck's constant, h = 6.626 x 10-34 Js
Rydberg constant, Rh= 2.18 x 10·18 J
Speed of light, c = 2.998 x 108 ms-1
Inorganic Chemistry (ICH602S)
2nd Opportunity January 2025
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::::i
0....
PERIODIC TABLE OF THE ELEMENTS
QQ
a,
::::i
n
18
n::r
l
2
(1)
3
-v,.<..i'..,..
H
1.00794 2
34
13
14
15
56 7
He
16
17 4.00260
8 9 10
n
eI n
0
Li Be
6.941 9.01218
N
11 12
B C N 0 F Ne
10.81 12.011 14.0067 15.9994 18.9984 20.179
13 14 15 16 17 18
Na Mg
Al Si p s Cl Ar
22.9898 24.305 3
4
5
6
7
8
9
10
11
12 26.9815 28.0855 30.9738 32.06 35.453 39.948
19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
39.0983 40.08 44.9559 47.88 50.9415 51.996 54.9380 55.847 58.9332 58.69 63.546 6538 69.72 72.59 74.9216 78.96 79.904 83.8
37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
Rb Sr y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe
N
:,
C.
85.4678 87.62 88.9059 91.22 92.9064 95.94 (98) 101.07 102.906 106.42 107.868 112.41 114.82 118.69 121.75 127.6 126.9 131.29
0
55 56 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86
"O
"O
0.,....,..
C
Cs Ba Lu Hf Ta w Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
132.905 137.33 174.967 178.49 180.948 183.85 186.207 190.2 192.22 195.08 196.967 200.59 204383 207.2 208.908 (209) (210) (222)
:;:::::i;:
87 88 103 104 105 106 107 108 109 110 111 112
114
116
118
-<
'a-,
Fr Ra Lr Rf Db Sg Bh Hs Mt Uun Uuu Uub
Uuq
Uuh
Uuo
::::i
C
(223) 226.02S (260) (261) (262) (263) (264) 1265) '268) (269) (272) (269)
-a.<,...
N
0
N
LT1
Lantbanides: 57 58 59 60 61 62 63 64 65 66 67 68 69 70
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
138.906 140.12 140.908 144.24 (145) 15036 151.96 157.25 158.925 162.50 161.930 167.26 166.934 173.04
Actinides:
89 90 91 92 93 94 95 96 97 98 99 100 101 102
u Ac Th Pa
Np Pu Am Cm Bk Cf Es Fm Md No
227.028 232.038 231.036 238.029 237.048 (244) (243) (247) (247) (251) (252) (257) (258) (259)