HCS chemistry optional question paper 2011 Frontier IAS

HCS chemistry optional question paper 2011

HCS Mains-2011 CHEMISTRY Code-04

Time: 3 Hours                      Maximum Marks: 150

Note: Attempt FIVE questions in all. All questions carry equal marks. Question No. 1 is compulsory. Answer two questions from part —I and two questions from part —II. The parts of the same question- must be answered together and must not be interposed between answers to other questions.

1.Write notes on any FIVE of the following: (5 X 6 =30)

a) Lanthanide Contraction

b) Radius ratio rule

c) Conducting Polymers

d) Solvent effect in reaction mechanism of organic compounds

e) Jahn Teller Effect

f) Fluoresence and phosphorescence

g) IR Spectroscopy

PART-I

2.                                      (5 + 5 =10)

a)

i) Write down the Schrodinger wave equation for wave mechanical model of an atom.Name the three quantum numbers of an electron which are yielded by the equation.Explain signi?cance of each quantum number.

ii) Discuss the departure of real gases from ideal behaviour

• When Pressure is not too high.
• When pressure is too high.

b) Explain the reasons: (4 X 2.5 = 10) 

1.SO2 has dipole moment while CO2 does not

2.NF3 has zero dipole moment but NF3 has high value of dipole moment.

3.LiCl has a higher boiling point than HCl why

4. AgF, AgCl and AgBr have similar structures. Explain their hardness.

c) Explain the following: (5+5 = 10)

1. Schottky & Frenkel defects
2. Band Theory

3. a) (5+5=10)

i) Explain What do you understand by heat capacities Cp and Cv. Derive the relation between them.

ii) Explain Hess’s Law

b) Derive Clausius-Clapeyron equation in its integrated form and discuss its importance in phase equilibria giving at least two examples. (10)

c) Discuss brie?y with example main applications of electrochemical series. (10)

4.a)                                                                                          (5+5 = 10)

1. What is Beer Lambert’s law? Explain various terms involved in it.
2. Explain the term Quantum yield

b)                                                                                              (5+5 = 10)

I) Write the formula of the following:                                

Dibromodiaquodiammine cobalt (III) chloride

Tetrahydroxodiaquoaluminate (III) ion

II) Illustrate with an example each of the following, with respect to coordination compounds:

•  Linkage isomerism
•  Geometrical isomerism

c) Give a brief comparison between Collision theory and transition state theory. (10)

PART-II

5.

a)  Describe preparation and properties of Styrene and Nylon. (10)

b) Give the mechanisms of Reiemer Tiemann and Reformatsky reactions. (10)

c) Explain in respect of NMR spectroscopy: (5 +5 =10)

• Chemical shift.
• Shielding and deshielding of protons.

6.

a) De?ne spectroscopy and explain its basic principle. Differentiate the energy levels for electronic, vibrational and rotational energy changes. (10)

b) Define the terms reduced viscosity and intrinsic viscosity. Explain how you can determine the molecular mass of the polymer from viscosity measurements. (10)

c) Give the mechanisms of Pinacol—pinacolone and Beckmann rearrangements. (10)