Guru Nanak Dev University 2007-3rd Sem B.Sc Chemistry CHEMICAL BONDING (Chem-301) (, 2k7) - Question Paper
Tuesday, 22 January 2013 07:15Web
2117
B.Sc. (H.S) (Third Semester)
CHEMISTRY
Paper - Chem-301
(Chemical Bonding)
Time Allowed : three hours
Maximum Marks : 75
part - A
Note : Attempt ALL the ques. from this part. every ques. carries 1½ Marks.
(10 x 1½ = 15)
1.
(i) provide general characteristics of ionic compounds.
(ii) How does radius ratio help in determining the coordination number of solids ?
(iii) discuss the significance of born-Haber cycle.
(iv) refer to attachment at the end of ques. paper
(v) refer to attachment at the end of ques. paper
(vi) Show by means of a diagram how the trend of d orbital splitting modifications as octahederal complex undergoes tetragonal distortion and eventually becomes a square planar complex.
(vii) How does the nature of ligand affect the magnitude of CF splitting ?
(viii)Define superconductivity. What kinds of materials are superconductors ? provide potential uses of superconductors.
(ix) elaborate the limitations of valence bond theory ?
(x) discuss the terms conductors, semi-conductors and insulators.
part - B
Note : Attempt any 8 ques. from this part.
(8 x 4½ = 36)
2. How is bond order assigned for a diatomic molecule in MO theory ? Illustrate your answers giving suitable examples.
3. define the rules for obtaining hybrid orbitals on the basis of group theory.
4. refer to attachment
5. define different kinds of defects that occur in solid state. provide suitable examples in every case.
6. Draw and define the crystal structures of zinc blende and courtzite in terms of close packing and occupancy of tetrahederal and octahederal holes.
7. Write an explanatory note on electroneutrality principle.
8. refer to attachment
9. refer to attachment
10. define Fajan's rules.
11. define the use of Jahn-Teller theorem in explaining the distortions in structures of elecrically degenerate systems.
12. discuss nephelauxetic effect.
13. define spectrochemical series.
part - C
Note : Attempt any 2 ques.
14. explain thermodynamic effects of crystal field slitting in transition metal complexes. (12)
15. Write notes on :-
(a) Band theory of metallic bonding.
(b) Angular overlap model. (6,6)
16. Derive Born-Lande formula and describe the terms in it. explain its importance by selecting examples.
17. Refer to attachment
SECTION A
1.
(iv) Give valence bond representation for BeCl2.
(v) Draw and describe the structure of XeF6 based on VSEPR theory.
SECTION B
4. Determine the wave functions of sp3, sp3d and sp3d2 hybridizations.
8. Discuss using VBT as well as CFT why NiCl42- is paramagnetic while [Ni(CN)6]4- is diamagnetic.
9. Define the term hybridization. Explain the geometry of ClF3, BrF5 and IF7 molecules.
SECTION C
17. Discuss molecular orbitals formed in octahederal metal complexes having σ as
well as π bonding.
| Earning: Approval pending. |
