CSS Chemistry Past Paper 2016

Instructions specific to this paper

• Attempt ONLY FOUR questions from PART-II. ALL questions carry EQUAL marks.
• Use of Calculator is allowed.
• Attempt ONLY FOUR questions from PART-II. ALL questions carry EQUAL marks.

Questions

1. Q. 26 marks

   (a) What is Schrodinger wave equation? Discuss its importance in quantum chemistry. (b) Solve the Schrodinger wave equation for a particle in three-dimensional box and (8) find the expression for the energy and wave function. (c) What is a well-behaved function? What are the requirements of a physically (6) acceptable wave function?

2. Q. 36 marks

   (a) What is Gibbs free energy? Discuss its significance in chemistry. (b) Give a brief account of transition state theory indicating its advantages over (8) collision theory. (c) Explain 3rd law of thermodynamics. How this law is useful to determine the (6) absolute value of entropy?

3. Q. 46 marks

   (a) Define and explain Langmuir adsorption isotherm. What are its limitations? (8) (b) What is acid-base catalysis? Discuss its significance in chemistry. (c) What is Phase rule? Discuss its application in one component system. (6)

4. Q. 58 marks

   (a) What are solubility product and common ion effect? Discuss their significance in chemical analysis (b) Valence shell electron pair repulsion theory can be used to predict the shapes of (7) molecules. Using this theory explain the shapes acquired by BF3 and IF5. (c) Explain why HSH bond angle in H2S is slightly less than the tetrahedral angle (5) 109.5

5. Q. 66 marks

   (a) Describe main features of crystal field theory, How this theory explains colour (10) of coordination complexes? (b) Write the electronic configuration for each of the following: (4) Ni2+ , Cu, Mn 2+ , Cr 3+ (c) What is John-Teller theorem? Explain its significance in coordination chemistry.

6. Q. 720 marks

   Write a brief account on the following: (5 each) (a) Biological importance of starch (c) Primary structure of Proteins (b) Classification of Amino acids (d) Glycogenesis

7. Q. 84 marks

   (a). Differentiate following using IR Spectroscopy? i H3C CH3 CH3 H3C H3C NH2 NH N CH3 O O O H3C O CH3 ii H3C OH H3C CH3 iii H3C CH2 CH3 H2C CH CH3 HC C CH3 iv H3C CH2 CH2 CH3 CH2 CH2 (b). What type of electronic transition are possible in the following compounds? (2) (i) Butadiene (iii) Acetaldehyde (ii) Diethyl ether (iv) Trimethylamine (c). How will you distinguish the following compounds using UV/Visible (4) spectrophotometer? NO2 (i) and (ii) and O O O H3C C CH CH2 (iv) and O H3C C CH2 CH3 (iii) CH2 and CH 3 (d). Give the chemical shift of the following compounds for each proton (5) H3C CH3 H CH3 H Cl C C C C C C H3C CH3 (ii) H CH3 ( H CH3 (i) H3C Cl H3C C CH2 Br (v) (iv) CH3 (e). The mass spectrum of compound shows following peaks: (5) m/e= 120, relative intensity=20% (M+ peak), m/e= 105, relative intensity=80%, m/e= 77, relative intensity=96%, m/e= 43, relative intensity=35%. Assign the structure which would be expected.

Standard FPSC instructions

Printed on this and every CSS paper.

• Part-II is to be attempted on the separate Answer Book.
• All the parts (if any) of each question must be attempted at one place instead of at different places.
• Write Q. No. in the Answer Book in accordance with Q. No. in the question paper.
• No page/space be left blank between the answers. All the blank pages of the Answer Book must be crossed.
• Extra attempt of any question or any part of the attempted question will not be considered.