Time Allowed: 3 hours Maximmn Marks: 300
Candi dates should attempt Question Nos. 1 and 5 which are compulsory, and any three 0 f the remaining questions selecting at least one question from each Section. Assume suitable data if considered necessary and indicate the same clearly.


SECTION A

1. Answer any three 0f the fo110wing

State and explain Heisenberg's uncertainty principle. "Why is it not applicable to large partic1es.

"When an electron was accelerated through a potential difference of 1.00 ± 0.01 kilovolt, what is the uncertainty of position of the electron along its line of projection?


How does the principle of 'maximum overlap' explain the stability of a chemical bond? Enumerate the essential condition.

"What is atomi c radius 0f a cubic latti ce? Find the atomic packing factor in simple cubi c system, body-centered cubic system and face-centered cubic system.

A perfect monatomic gas is expanded reversibly and adiabatically at 300 K from a pressure of 106 Fa to 10 Fa "What is the final temp erature? How much work can be done?

2. "What is meant by electron probability function? Draw the radial distributi0n curves for is, 2S, 2p, 3s, 3p and 3d electron and exp1ain radi al nodes, radius 0f maximum probability and penetrating power of electrons.

"What is the essential difference between ionic bond and covalent bond? Explain why watermolecule is non-linearwhilemethane mo1eculeistetrahedral.

"What is lattice energy? Describe how lattice energy of an ionic solid is evaluated by Born Haber cyc1e.

State and explain Maxwells law 0f distribution of velo cities 0 f molecules 0f a gas at a definite temperature. What is meant by most pro bable velocity?

3. "What are semiconductors? Explain n -type and p-type semiconductors. Discuss the effect of temperature on semiconductors.

Derive the Kelvin equation for the vapour pressure 0 f droplets and bubbles.
"What are nuc1eation centres? Indicate their importance.

Explain the criteria of equilibrium and spontaneity in terms ofU, A and G.

4. "The third law 0 f Thermos dynami cs states an impo ssibility." Justify thi s statement.

Explain why the molar entropy of Ice aystals approaches 335 JK'mor" as the temperature approaches zero kelvm

Define Chemical potential. Explain its Slgnificance Deduce equations for the vanation of chenucal potential with temperature and pressure


What ls the maximum number of phases that can be in equlibrium at constant pressure and temperature in two-and three-component systems?

For the reaction 3H2 2NH3(g) Kp 164 X10-4 at 670 K. Calculate deltaG'

SECTION B

5. Answer any three of the following
Define activity, activity co efficient and mean activity co efficient 0f Ions in solution Denve and use the Debye-Huckellimiting 1aw for mean activity coeffiCIent, and indicate how it can be extended to more concentrated solution

Derive an equation to relate temperature on rate of reaction and calculate the energy of activation


"Tetrahedral complexes of 3d transition metals are always of high spin." Justify the statement

Calculate the crystal field stabilisation energy and spin-only magnetic moment of


"Actillldes are more prone to complex fonnation than lanthanides." Justify the statement
Explain why ZlrCOlllum and hafnium occur together in nature


6 What lS first-order reaction? Deduce an equation for first-order reaction and show that its half-hfepen odlSmdependent 0f them itial concentration of the reactant

With neat diagram, describe
lead aCId ballery with discharge and charging reactions;
fuel cell with anodic and cathodic reactions 10=20)

State and explam the law of photochemical eqUivalence How are the discrepanCIes of this law explained?


7 What are heterogeneous catalysts? Discuss the charactensti cs and mecharu sim of reaction on heterogeneous catalysts

Identify one Slgnlficant role m biological processes for each of the following elements Fe, Mg, Zn, 1
How lS Iron stored and transported in maimmals? WhatlS the oXidation state of Iron for storage and transfer?

"The complex [NiCl4]2- is paramagnetic whereas is diamagnetic" Justify the observations
Explain the origin of pale pink colour of

8 Explain the possible lSomerism in the following complexes
[Co(NH3l5Br] SO4
[Co(Nfu)5NO2j
[Co(en)2Cl2]

"The trans-effect senes has proved very useful m rational1smg known synthetic procedures and in devlSing new ones." Justify the statement with suitable examples

Explain with the 31d of suitable diagrams how CO fonns Sigma and pi bonds m Apply EAN rule to


Explain the structure and bonding in iodine penlafluonde and polythiazyl