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LOYOLA COLLEGE (AUTONOMOUS), CHENNAI 600 034
B.Sc.DEGREE EXAMINATION -CHEMISTRY
SIXTH SEMESTER APRIL 2018
CH 6612- MOLECULAR DYNAMICS
Date: 17/04/2018 Dept. No. Max. 100 Marks
Time: 09:00-12:00
PART A
Answer ALL questions. (10 x 2 20 marks)
1. Define the term orbit and orbitals.
2. State Pauli's exclusion principle.
3. Calculate the energy of the photon associated with light of wavelength 3000Ao.
4. Define the term degeneracy of an energy level.
5. Find the value of ln100!
6. What are micro states?
7. State Beer-Lambert law.
8. Explain intersystem crossing.
9. The optical density of 0.001 M solution in a cell of 0.1 cm path length is 0.162.
Calculate the extinction coefficient.
10. Define quantum yield.
PART B
Answer any EIGHT questions. x 5 40 marks)
11. How is photoelectric effect explained by quantum theory?
12. Explain the energy distribution in Black Body radiation.
13. State the postulates of quantum mechanics.
14. Explain the emission spectrum of hydrogen atom.
15. Derive the energy equation for butadiene.
16. Calculate the translational partition function of NO molecule at 300 K in a volume 1000 m3. Assuming the gas to behave ideally.
17. Calculate Strans for nitrogen gas at one atm. pressure and at 30oC.
18. Explain the primary and secondary processes in a photochemical reaction.
19. Explain chemical actinometers with an example.
20. A sample of gaseous HI was irradiated by light of wave length 253.7 nm when 307 J of energy was found to decompose 1.30 x 10-3 mole of HI. Calculate the quantum yield for the dissociation of HI.
21. Discuss the process of photosensitization.
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22. In the photochemical combination of hydrogen and chlorine a quantum efficiency of 1 x 106 is obtained with a wavelength of 480 nm. How many moles of hydrogen chloride would be produced under these conditions per joule of radiation energy absorbed?
PART C
Answer ANY FOUR questions. x 10 40 marks)
23. What are quantum numbers? Give its significance.
Explain Bohr's theory of atom.
24. Calculate the de Broglie wave length of a body of mass 1 kg moving
with a velocity of 2100 ms-1.
Derive the expressions for eigen value and eigen function for a particle
in one dimensional box.
25. Derive Maxwell-Boltzmann statistics. Give its application.
26. Derive an expression for translation partition function.
Discuss the kinetics of photochemical reaction of H2 and Br2.
27. Explain any two of the following:
Phosphorescence Chemiluminescence
Relaxation Technique Jablonski'sdiagram(10)
28. Derive Stern-Volmer equation. Give its applications.