LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034
B.Sc. DEGREE EXAMINATION – CHEMISTRY
SIXTH SEMESTER – APRIL 2006
CH 6600 – MOLECULAR DYNAMICS
(Also equivalent to CHE 600)
Date & Time : 19-04-2006/FORENOON Dept. No. Max. : 100 Marks
PART – A
Answer ALL questions. (10 ´ 2 = 20 marks)
- State the de Broglie relation. Explain the condition under which it is applicable.
- Normalise eax in the interaval (0,1).
- What are the possible values for angular momentum according to Bohr’s postulate?
- Give the expressions for wave function and energy for the third p-energy level of 1,3-
- Evaluate ln N! when N = 1030 using Stirling’s formula.
- Calculate the number of ways of distributing four particles among five energy levels if the particles are electrons.
- Write Boltzmann equation connecting entropy and thermodynamic probability.
- What is intersystem crossing?
- Define quantum yield of a photochemical reaction.
- Mention any four relaxation methods used in the kinetic study of fast reactions.
PART – B
Answer any EIGHT questions. (8 ´ 5 = 40 marks)
- Determine the kinetic energy of the electrons emitted by a light of 100 nm if the threshold frequency of the metal is 9.0 ´ 1014
- Calculate the ionization energy per mole of H atom.
- Derive the expression for Hamiltonian operator in cartesian coordinates.
- Examine whether “A sin ax” is Eigen function for the second order differential operator. If so, state the Eigen value.
- Calculate the wave length of transition for a conjugate olefin containing 3 double bonds.
- Explain how partition functions can be separated.
- Calculate the ratio of translational partition function of D2(g) to H2(g) at the same temperature and volume.
- Write Sackur-Tetrode equation and mention the terms involved.
- Derive the relation connecting internal energy(E) and molecular partition function(Q).
- Explain the principle of flash photolysis.
- Explain the factors affecting phosphorescence emission.
- Explain photosensitisation with two examples.
PART – C
Answer any FOUR questions. (4 ´ 10 = 40 marks)
- Obtain an expression for the radius of “H” atom on the basis of the Bohr’s model of atom.
- Obtain the expressions for the energy and wave function of a free particle in a one dimensional box.
- State the postulates of Maxwell-Boltzmann distribution law and hence derive an expression for most probable distribution.
- Explain any two of the following
(a) Fluorescence and structure
- Kinetics of H2-Br2 (photochemical) reaction.
- Chemical actinometer.
- Draw Jablonski diagram and explain in detail.
- Derive the following
(a) E = RT2
(b) Etranslation =