B.Sc. 2nd Year Chemistry Question Papers 2021 BRABU Muzaffarpur

B.Sc. 2nd Year Chemistry Question Paper-III & IV, Examination- 2021, BRABU Muzaffarpur

Here you can find B.Sc. Honours 2nd Year Chemistry Previous Year Question Paper-III & IV, BRABU Muzaffarpur

Paper-III

Note: Candidates are required to give their answer in their own words as practicable. Answer any five questions, selecting two questions from Group-A and three from Group-B.

Group - A [25 Marks]

1. (a) Derive an expression for the rate constant of a first order reaction.
(b) Show that half life period of a 1st order reaction is independent of initial concentration.
(c) Half life period of a 1st order reaction is 100 days. How long will it take for its 90% completion?

2. (a)State and explain Maxwell law of distribution of the molecules at definite temperature.
(b) Discuss the effect of temperature on velocity distribution.
(c) Differentiate between average velocity and most probable velocity.
3. (a) What is Salt hydrolysis? Calculate the pH of a salt formed by strong acid and weak base?
(b) Explain Buffer solution. Show that Sodium acetate solution is not a buffer by itself.

4. Write explanatory notes on the following: (any three)
(i) Concept of electrode potential.
(ii) Solubility product and its application.
(iii) Calomel electrode.
(iv) Homogeneous and Heterogeneous Catalysis.
(v) Types of electrodes.

Group - B [50 Marks]

5. Define transition elements. Discuss the general characteristics of 3d-transition series with respect to following:
(i) Variable oxidation state
(ii) Magnetic behaviour
(iii) Complex forming ability
(iv) Formation of coloured ions.

6. Explain the following giving reasons (any four)
(i) Liquid ammonia solution of sodium is blue, paramagnetic and conducting.
(ii) NH₄Cl behaves as a strong acid in liq. NH₃.
(iii) H₂O is a liquid but H₂S is a gas.
(iv) Transition metals are less reactive than alkali and alkaline earth metals. (v) The metals of second transition series show higher oxidation states than the metals of first transition series.
7. (a) Discuss the structure and bonding in Copper acetate.
(b) Draw the resonating structure of NO⁻ and PO₄⁻

8. (a) Discuss valence bond theory of bonding in coordination compound.
(b) Write IUPAC nomenclature of the following:
(i) [Co(NH₃)]⁺³
(ii) [Co(NH₃)₄ (OH)₂Cl₂
(iii) [Rn(en)₃ ](NO₃)₂
(c) Explain why [Fe(CN)₆]⁻⁴ is diamagnetic but [Fe(CN)₆]⁻³ is paramagnetic.
9. Write short notes on any three of the following:
(i) Use of Na₂S₂O₃ solution in volumetric analysis.
(ii) Use of 8-hydroxyquinoline
(iii) EAN rule
(iv) Inner complex

Paper-IV

Note: Candidates are required to give their answer in their own words as practicable. Answer any five questions, selecting two questions from Group-A and three from Group-B.

Group - A [25 Marks]

1. (a) State and explain second law of thermodynamics.
(b )Explain Gibbs energy and its significance. How does it vary with pressure and temperature?

2. (a) Differentiate between:
(i) True solution, colloids and suspension.
(ii) Lyophilic and Lyophobic colloids.
(b) Explain Hardy-Schultz law.
3. (a) State and explain Raoult's law for vapor pressure of binary solutions of volatile liquids.
(b) Enumerate the factors influencing the solubility of gas.
(c) Raoult's law may be taken as a special case of Henry's law. Explain.

4. (a) Write explanatory notes on the following: (any two)
(i) Origin of charge on colloidal sol.
(ii) Practical application of distribution law.
(iii) Claussius-Clapeyron equation and its application.
(iv) Principle of steam distillation.

Group - B [50 Marks]

5. Discuss the isolation of Citric acid from its source. Establish the structure of citric acid. How will you synthesise citric acid from acetone? How does citric acid react with HI?

6. Discuss the following reactions with mechanism:
(i) Perkin reaction
(ii) Cannizzaro reaction
(iii) Reformatsky reaction
(iv) Nitration of benzene
7. (a) How would you prepare the following from benzene diazonium chloride:
(i) Phenyl hydrazine
(ii) Benzoic acid
(b) Starting from diethyl malonate how will you obtain the following:
(i) Glutaric acid
(ii) Acetic acid

8.(a) Establish the open chain structure of D-glucose.
(b) How will you convert an aldopentose into aldohexose and vice-versa?
(c) Explain Mutarotation.
9. Write short notes on any three of the following:
(i) Huckel's rule of aromaticity.
(ii) E and Z system of nomenclature in Geometrical Isomerism.
(iii) Conformation of methyl cyclohexane.
(iv) Newman Projection formula of n-butane.
(v) Optical isomerism in Lactic acid.