BSc Chemistry SEM III ATKT Mar 2019 CHEMISTRY PAPER I Question Paper - Mumbai University | munotes

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1. Q1 All Questions are compulsory
2. Q2 Figures to the right indicate full marks
3. Q3 The use of log-table/nonprogrammable calculator is allowed
4. Q4 Answers for the same question as far as possible should be written together
5. Q1 (A) Select the correct option and complete the following sentences 12 marks
   • (i) The escaping tendency of real gases is represented If for a reaction is greater than zero then For a pure substance, chemical potential is equal
   • (iv) Degree if ionization of an electrolyte depends on
   • (a) Only nature of electrolyte (b) only presence of (c)
   • (v) The SI unit of cell constant is
   • (a) cm m'! (c) m!
   • (vi) If a transport number of K* is 0.492 in KCI solution. The transport number of will (vil) Geometry of SF4 molecule is Kapustinskii equation is used energy
   • (ix) Bond order in O2 molecule
   • (x) NaCl crystal is of of crystal system
   • (xi) The three equatorial chlorine atoms in PCI5 molecule are at with respect to each other Coordination number of each ion in NaCl crystal is
   • (xiii) Alcohols react with Grignards reagent forming
   • (xiv) The phenoxide anion occurs in canonical forms
   • (xv) Alkyl lithium reacts with formaldehyde in presence of ether to form a product which on hydrolysis
   • (xvi) Cine substitution is observed (xvil) Phenyl magnesium chloride on treatment with water Elimination addition mechanisms are possible in the presence of
   • (c)weak nucleophile
   • (B) State whether the following sentences are True or False(any three) 03
   • (i) For strong electrolytes degree of dissociation is nearly equal to one Activity coefficient is always less than one Lesser the number of resonating structures, the greater is stability of
   • (iv) The regular geometry for sp*d* type of hybridisation is square
   • (v) SN' reactions are favoured by less polar solvents
   • (vi) Dows process is the method used for preparation of phenol from Sodium and alkyl halide
   • (C) Match the following(any five) 05
   • (v) and acidic | (e) intensive property
   • (g) Reciprocal Attempt any four of the following
   • (B) The equilibrium constant for a gaseous reaction is 170 at 500 K 05 heat of reaction is — 42.676 kJ. Calculate equilibrium constant at 700
   • K. (Given R = 8.314J )
   • (C) Explain variation of free energy with temperature and pressure. 05
   • (D) Discuss the determination of solubility and solubility product of 05 sparingly soluble salt by conductometric method
   • (E) What do you meant by limiting molar conductance? How is it 05 determined for strong and weak electrolyte?
   • (F) In the moving boundary method, for determination of transport 05 number of potassium ions in 0.1mol dm? of the boundary moved through a distance of 7.2 cm ina tube of the cross sectional area of 0.112 cm?A current of 0.0065 amperes passed for 2400 seconds was responsible for the movement of the boundary Calculate the transport number of K* ion. (F=96500 Attempt any four of the following
   • (A) Define the terms: i.sigma(o) molecular orbital 111. 05 Hybridisation. Explain any one in detail
   • (B) Draw molecular orbital diagram of Bz molecule. calculate its bond 05 order and state magnetic property
   • (C) Explain the shape of XeF4 molecule on the basis of covalent bonding, 05
   • (D) With suitable example represent Born —Haber cycle for the formation 05 of ionic compound. Mention the energies involved in each step
   • (E) On the basis of LCAO method explain the formation of Bonding 05 molecular orbital and Antibonding molecular orbital
   • (F) Find the electron affinity of iodine using Born Haber cycle with the 05 help of following data Heat of formation of Nal = -287.9 kJ/mol, Heat of sublimation of Ionisation energy of sodium= 493.8 kJ/mol, Lattice energy of Nal=
6. Q4 Attempt any four of the following
   • (A) What is elimination addition mechanism ? Give the mechanism of 05 action of sodamide (NaNHz2). in liquid ammonia on chlorobenzene
   • (B) How will you obtain phenol from Benzene sulphonic acid ? Why is 05 phenol a weak acid ? What will be the products formed when phenol is treated with
   • i)dil HNO3
   • (C) What is an organo metallic compound ? How will you synthesize the 05 following, give any one method
   • a) Lithium Why are both the compounds given above prepared under anhydrous
   • (D) Complete the following reactions 5
   • b) Cl
   • (E) What are alcohols ? How are they classified ? Give examples. 05 From ethanol how will you prepare the following , giving reactions
   • (F) How will you synthesize the following , giving reactions only 5
   • (a)Acetic acid from Ethanol
   • (b)Ethylene oxide from ethylene chlorohydrin
   • (c)Sodium phenoxide from Phenol
   • (d)Triethanol amine from ethylene oxide chloride from methanol
7. Q5 Attempt any four of the following
   • (A) Derive an expression for Van’t Hoff’s reaction isotherm. 05
   • (B) What do you meant by a cell constant of a conductivity cell? 05 How is it determined experimentally?
   • (C) Give an account of corrections applied to H2 molecule with respect to 05
   • (D) Justify:- Beryllium molecule is not expected to exist according to 05
   • (E) Explain the mechanism of alkaline hydrolysis of methyl bromide 05 giving the energy profile diagram and stereochemistry of the products
   • (F) How will you convert the following 5
   • (a)Ethylene oxide to ethylene cyanohydrin
   • (b)Phenol to picric acid
   • (c)Methyl magnesium bromide to acetone
   • (d)Methyl chloride to methyl lithium
   • (e)Methanol to acetate

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