BSc Chemistry SEM V 2018 19 2018-19 Chemistry I Physical Chemistry 19 Old Question Paper - Mumbai University | munotes

Questions asked in this paper

• (2) Figures to the right indicate full marks

1. Q1 Attempt any three of the following:
   • (A) Define: Freezing point. A solution containing1.44g of non-volatile solute in 5 100g of water boils at 373.12K.Calculate the molecular weight of the solute (Given: Boiling point of water=373K,
   • (B) State Gibb’s Phase Rule and explain the terms involved in it. 5
   • (C) Explain the triangular phase diagram for a three component system. 5
   • (D) Discuss the application of the phase rule to the water system with the help 5 of a neat labelled diagram
   • (E) Derive Van’t Hoff equation for Osmotic pressure. 5
   • (F) What concentration of a substance in water is needed, so that the 5 resulting solution boils at372.09 K (Given: Boiling point of water=373K,
2. Q2 Attempt any three of the following:
   • (A) Explain the kinetics of acid catalysed reactions. 5
   • (B) Define adsorbate. Explain any two types of adsorption isotherms. 5
   • (C) The volume of gas adsorbed reduced to STP was found to be 126 of 5 the adsorbent. Assuming that molecules are closely packed in the first layer, calculate the surface area of the adsorbent if each gas molecule occupies
   • (D) Name the four electrokinetic phenomena and explain in detail any one of 5
   • (E) (i) Draw the diagram for Stern’s model of the electrical double layer and 3 give the expression for zeta potential
   • (ii) Explain the terms homogenous and heterogenous catalysis. 2
   • (F) Give a detailed classification of surfactants. 5
3. Q3 Attempt any three of the following:
   • (A) Give a detailed classification of cells with suitable examples. 5
   • (B) State any three merits and two demerits of quinhydrone electrode. 5
   • Q.P.Code: 38707
   • (C) A solution is 0.02m with respect to KCI and each.Calculate the 5 activity coefficient of KCI in this aqueous solution (A=0.509 at 298 K)
   • (D) Derive an expression for emf of electrode concentration cell without 5 transference reversible to cations
   • (E) What is meant by liquid junction potential? How does it arise? How is it 5
   • (F) Calculate the solubility of in mol in pure the standard 5 oxidation potentials of and are —0.124V
4. Q4 Attempt any three of the following:
   • (B) In a polymer sample 20 % of the molecules have molecular weight 5 20,000, 30 % have 45,000 and the rest have molecular weight 40,000 Calculate weight average and number average molecular weights
   • (C) Write a short note on light emitting polymers. 5
   • (D) Name the laws of crystallography. Write with the help of diagrams, explain 5
   • (i) Axis of Symmetry. (ii) Centre of symmetry
   • (E) The angle of reflection for first order diffraction pattern from (110) plane 5 of a cubic crystal is Calculate the inter planar distance between two (110) planes, if the wavelength of the incident X-ray front is m
   • (F) Explain the terms (i) relative viscosity (ii) specific viscosity 5 5.(A) State True or False:- 4
   • (a) Sulphur has four triple points
   • (b) When solute particles associate i is less than unity
   • (c) In Pb-Ag system the eutectic composition of Ag is 2.6% at
   • (d) CaCO3 system is a three component system
   • (A) Match the following 4
   • (B)State True or False 4
   • (a) Lyophilic colloids are more stable than lyophobic colloids
   • (b) A catalyst lowers the energy of activation
   • (c) Alkyl sulphonic acids are an example of colloidal electrolytes
   • (d) Promoters when added improve the catalytic activity of the catalyst
   • Q.P.Code: 38707
   • (B) Match the following 4
   • (v) Hydrolysis of methyl acetate
   • (C) State True or False 4
   • (a) Salt bridge is used to eliminate liquid junction potential
   • (c) Debye Huckel limiting law is applicable to strong and weak electrolytes
   • (d) In chemical cell the two electrodes are chemically different
   • (C ) Match the following 4
   • (D) State True or False 3
   • (b) In Frenkel defect hole is formed in the lattice
   • (D) Match the following 3
   • (p) X-rays (i) 23 elements of symmetry
   • (r) Body Centred Cubic lattice (iii) Four atoms belong to unit cell
   • (iv), Two atoms belong to unit cell

Read from the scan above, so a character or two may differ. The scan is the original.