Saturday, September 09, 2017

Dibrugarh University Question Papers: Inorganic Chemistry - (Inorganic, Physical and Organic)' 2016

2016 (November)
CHEMISTRY
(General)
Course: 101
(Inorganic, Physical and Organic)
(New Course)
Full Marks: 80
Pass Marks: 24
Time: 3 hours
The figures in the margin indicate full marks for the questions
SECTION – A
(Inorganic Chemistry)
(Marks: 27)


1. Choose the correct answer: 1x3=3

  1. Which of the following ions is paramagnetic in nature?
  1. Zn2+
  2. Cu2+
  3. CI-
  4. Sc2+
  1. Which of the following compounds is non-polar?
  1. H2O
  2. NH3
  3. BCI3
  4. HCI
  1. The hybridization involved in H2O is
  1. Sp2
  2. Sp3
  3. Sp3d
  4. Sp3d2
2. Answer the following questions: 2x3=6
  1. Among halogens, CI has the highest electron affinity. Explain.
  2. Predict the structure of XeF6 molecule using VSEPR theory.
  3. What is lattice energy? How lattice energy controls the solubility of ionic.


3. Answer any two questions of the following: 3x2=6
  1. Define hydrogen bonding. The density of water is maximum at 4 0C. Explain. 1+2=3
  2. Write down the electronic configurations of the following ions: 1+1+1=3
  1. Ti2+
  2. S2-
  3. Co2+
  1. What is the linear combination of atomic orbital (LCAO)? Show with the help of LCAO the formation of bonding and anti-bonding molecular orbital’s formed by 2p-orbital. 1+2=3
4. Answer any three questions of the following: 3x3=9
  1. What is electronegativity? Write briefly about Allred-Rochow scale of electronegativity. 1+2=3
  2. What is hybridization? Give example of each of sp2 and sp3d2 hybridization. 1+2=3
  3. What is polarizing power of a cation in ionic compound? Among the halides of sodium, which one is most covalent and why? 1+2=3
  4. Write down the molecular orbital configuration of O2. Find its bond order and mention its magnetic property. 1+1+1=3
5. Write short notes on the following: 1½ x 2 = 3
  1. Effective nuclear charge.
  2. Resonance energy.
SECTION – B
(Physical Chemistry)
(Marks: 26)
6. Choose the correct answer:
  1. The ratio of the root-mean-square speed of H2 at 50 K and that of O2 at 800 K is
  1. 4
  2. 2
  3. 1
  4. 1/4
  1. The vapour pressure of a liquid does not depend on which of the following factors?
  1. Temperature.
  2. Density.
  3. Presence of solute.
  4. Intermolecular attraction of liquid molecules.
  1. The crystal defect which may occur in NaCI crystal is
  1. Frenkel defect.
  2. Schottky defect.
  3. Impurity defect.
  4. None of the above.
7. Answer either question (a) or (b): 5
(a) (i) Define root-mean-square speed of gas molecules. 1
(ii) Define compressibility factor. Explain the deviation of real gases from ideal behaviour in terms of compressibility factor. For CO2 gas at 273 K and 1 atm pressure, compressibility factor is 0.2007. Calculate the volume occupied by 0.1 mole of the gas at that temperature and pressure. 1+2+1=4
(b) (i) What do you mean by most probable speed of gas molecules? Calculate the most probable speed of CO2 gas molecules at 27 0C.
(ii) How van der Waals modified the volume term of ideal gas equation to apply it for real gases? 2
8. Answer any two questions of the following: 4x2=8
(a) (i) What is meant by collision frequency of gas molecules? How it changes with temperature of the gas? 1+1
(ii) How does viscosity arise in a gas? Explain how viscosity of gas changes with temperature. 1+1
(b) (i) Deduce critical constants from van der Waals’ equation. 3
(ii) State the law of equipartition of energy. 1
(c) (i) van der Waal’s constants for gaseous HCI are and. Calculate the critical constants of the gas. 3
(ii) Define reduced variable. 1
9. Answer either (a) or (b):
(a) (i) Define surface tension of a liquid. What is its SI unit? Explain how surface tension of a liquid varies with temperature. 1+1+1=3
(ii) At 293 K temperature time of flow for water and acetone in an Ostwald viscometer are 120.5s and 49.5s respectively. If at 293 K densities of water and acetone are and respectively and coefficient of viscosity of water at that temperature is 1.005 centipoise, then calculate the coefficient of viscosity of acetone. 2
(b) (i) What do mean by vapour pressure of a liquid? Explain how boiling point of a liquid depends on vapour pressure of the liquid. 1+1=2
(ii) Explain drop number method for determination of surface tension of a liquid in the laboratory. 3
10. Answer either question (a) or (b):
(a) (i) Write short notes on the following: 1½ x 2 = 3
  1. Axis of symmetry.
  2. Schottky defect.
(ii) Write Bragg’s equation. The diffraction of a crystal with X-rays of wavelength gives a first-order reflection at Calculate the distance between the lattice planes. (Given,)
(b) (i) What is unit cell? Cu forms f.c.c. crystals with edge length of the unit cell. Calculate the density of the metal. (Atomic mass of Cu is) 1+2=3
(ii) Describe the structure of CsCI crystal. 2


SECTION – C
(Organic Chemistry)
(Marks: 27)


11. Choose the correct answer: 1x4=4
  1. Which of the following is the correct increasing order of their acidity?
  1. Which of the following carbanions is most stable?
  1. Which of the following isomerism is shown by the lactic acid?
  1. Geometrical isomerism.
  2. Tautomerism.
  3. Optical isomerism.
  4. None of the above.
  1. In ethane molecule, the hybridizing state of both the C-atoms are
  1. Sp3
  2. Sp
  3. Sp2
  4. None of the above
12. Answer any three questions of the following: 2x3=6
  1. Define nucleophile and electrophiles. Give one example of each.
  2. Define inductive effect. “Formic acid is stronger than acetic acid.” Explain with the help of inductive effect.
  3. Write down the necessary conditions for an organic molecule to show geometrical isomerism.
  4. Define carbene. How is it classified?
13. Answer any four questions of the following: 3x4=12
  1. With the help of Newman projection formula, draw the possible conformations of n-butane molecule and give their names. Which is the most stable conformation of n-butane?
  2. Assign R- or S-configuration of the following:








  1. Draw the possible geometrical isomers of the following and assign them with E or Z:
  1. Write short notes on the following:
  1. Plane symmetry.
  2. Centre of symmetry.
  1. Define hyperconjugation. With the help of it, show that but-2-ene is more stable than but-1-ene.
14. (a) How n-pentane can be prepared with the help of Corey-House synthesis? 1
(b) Discuss the mechanism of chlorination of methane. 2
(c) How ethane can be prepared with the help of Kolbe’s electrolytic method? 2


(Old Course)
Full Marks: 80
Pass Marks: 32
Time: 3 hours
The figures in the margin indicate full marks for the questions
Write the answers to the separate Sections in separate books
SECTION – A
(Inorganic Chemistry)
(Marks: 27)


1. Choose the correct answer: 1x3=3
  1. Which of the following orbital is not possible?
  1. 2p
  2. 4d
  3. 6s
  4. 3f
  1. Which of the following bonds is non-polar?
  1. O – H
  2. CI – CI
  3. C – H
  4. H – F
  1. The hybridization of S in SF6 is
  1. Sp3
  2. Sp3d2
  3. Sp3d
  4. Sp2
2. Answer the following questions: 2x3=6
  1. The second ionization energy of an element is more than first ionization energy. Explain.
  2. Explain the shape of from VSEPR theory.
  3. The atomic number of four elements are 9, 11, 21 and 36
  1. Which one of them has the lowest ionization energy?
  2. Which one of them has the highest electron affinity?
3. Answer any two questions of the following: 3x2=6
  1. What is Pauli’s exclusion principle? Explain with suitable example. 1+2=3
  2. Write down the possible resonating structures of the following ions: 1+1+1=3
  1. Write down the molecular orbital configuration of ion. Find its bond order and mention its magnetic character. 1+1+1=3
4. Answer any two questions of the following: 4x2=8
  1. Write down the electronic configuration of the following:
  1. What is Fajans’ rule? Among the following, which one is most ionic and why?
  1. Write down the molecular orbital diagram of N2. Find its bond order and mention its magnetic properties. 3+1=4
5. Write short notes on the following: 2x2=4
  1. Hund’s rule.
  2. Resonance.


SECTION – B
(Physical Chemistry)
(Marks: 26)


6. Choose the correct answer: 1x3=3
  1. With the increase of temperature, the viscosity of a liquid
  1. Increases.
  2. Decreases.
  3. Remains same.
  4. First increases and then decreases.
  1. The number of atoms present in a unit cell of body-centred cubic lattice is
  1. 4
  2. 2
  3. 1
  4. 0
  1. The molecule having highest root-mean-square velocity at 27 0C is
  1. CO2
  2. CH4
  3. O2
  4. NH3
7. Answer any two questions of the following: 6½ x 2 = 13
  1. (i) Derive Boyle’s law from kinetic gas equation.
(ii) Mention two causes of deviation of real gases from ideal bahaviour. 2
(III) Using van der Waals’ equation, calculate the pressure of 1 mole methane which is kept in a 250 ml container at a temperature of 500 K. 2


  1. (i) Deduce the equation of corresponding states. 3
(ii) What is collision frequency? What is the effect of temperature on it? 2
(iii) What is Boyle’s temperature? Give its significance. 1+½=1½


  1. (i) What is critical phenomenon? Derive the expressions for the critical constants of a gas using van der Waals’ equation. 4
(ii) Show that
8. Answer any two questions of the following: 2½ x 2 = 5
  1. Explain the laboratory method for the determination of surface tension of a liquid.
  2. Define parachor. If the parachor values of butane and – CH2 – group are 190.2 and 39 respectively, then find the parachor value of carbon.
  3. Write how surface tension and viscosity of a liquid change with temperature. What is the SI unit of surface tension? 2+½=2½
9. Answer any one question of the following 5
  1. (i) Write two differences between amorphous solid and crystalline solid. 2
(ii) What is packing fraction? Calculate the packing fraction of a face centred cubic unit cell. 1+2=3


  1. (i) Gold has cubic crystals whose unit cell has an edge length of 407.9 pm. If the density of gold is, calculate the number of atoms in the unit cell of gold. Predict the type of crystal structure of gold. 3
(ii) Explain briefly the crystal structure of KCI. 2
SECTION – C
(Organic Chemistry)
(Marks: 27)


10. Choose the correct answer: 1x3=3
  1. Which of the following carbocations is most stable?
  1. Homolytic fission of a covalent bond results in the formation of
  1. Free radicals.
  2. Carbocations.
  3. Carbanions.
  4. Carbocation and carbanions.
  1. Which of the following compounds can exhibit geometrical isomerism?
11. Answer any three questions of the following: 2x3=6
  1. Define carbanions. Mention its stability order and reactivity order.
  2. Define nitrene. How is it classified?
  3. Explain the formation of acetylene molecule with the help of hybridization.
  4. Draw the chair conformation of cyclohexane showing equatorial and axial C – H bonds.
12. Answer any four questions of the following: 2x4=8
  1. With the help of Newman projection formula, draw the possible conformations of ethane and give their names.
  2. Assign R- or S-configuration of the following:

  1. Draw the possible geometrical isomers of the following and assign them with E or Z:
  1. Identify the chiral centres of the following and draw their possible optical isomers with the help of Fischer’s projection formula:
  1. Complete the following reaction and write down the rule involved in the reaction:
13. Answer any three questions of the following: 2x3=6
  1. State nitration of benzene and discuss the mechanism of the reaction.
  2. Convert ethyne into but-1-yne.
  3. Prepare propan-1-ol from propane with the help of hydroboration-oxidation reaction.
  4. Prepare n-pentane with the help of Corey-House synthesis.
14. Compute the following reaction (any four): 1x4=4







***

Labels

Absorption Costing (1) Accountancy (4) accounting for partnership firms (3) Accounting for Share Capital (3) accounts of non trading concern (3) advanced financial accounting (14) AHSEC (108) ahsec 11 (47) ahsec 12 (60) ahsec notes (104) AHSEC Question Papers (33) Assam Slet (10) bcfm (11) bills of exchange (6) branch accounting (3) Budgetary Control (3) Budgetary Control Notes (2) business communication (28) Business Environment Notes (12) business regulatory framewrok (49) Business Statistics Notes (25) cash flow statement (5) cbse 12 (19) cbse notes (27) commerce (13) company law (23) corporate accounting (33) corporate laws (14) cost accounting (63) cost and management accounting (34) cpt (36) cpt 200 (7) cpt notes (30) dibrugarh university (1113) dibrugarh university notes (597) dibrugarh university question paper (454) dibrugarh university solved papers (225) dibrugarh university syllabus (47) direct tax law (49) eco - 01 (4) ECO - 02 (2) ECO - 03 (2) ECO - 05 (6) ECO - 06 (1) ECO - 07 (1) eco - 08 (4) eco - 09 (1) ECO - 10 (2) ECO - 11 (3) ECO - 12 (7) ECO - 13 (2) ECO - 14 (4) entrepreneurship (14) fianancial accounting (3) financial accounting (48) Financial Accounting Notes (15) financial management (18) Financial statements analysis (14) funds flow statement (3) guwahati university (289) guwahati university syllabus (52) Hire Purchase (5) Human Resource Management (11) icwai (38) icwai notes (39) ignou solved assignments (83) ignou solved question papers (121) income from house property (5) income from salary (4) Income Under the head Salaries (11) information technology (10) Installment Purchase (4) issue of shares (4) kkhsou (13) M.com (62) Management Accounting Notes (31) MCQ (11) paper I (1) paper II (9) paper III (1) principle of business mangement (16) Principles of Marketing Notes (16) royalty accounts (3) sale of goods act (8) semester I (151) Semester II (154) semester III (81) semester IV (149) semester V (111) semester VI (91) slet (13) Slet Ne (10) Small Business Management (7) solved assignments (22) UGC - NET: Commerce (08) (14) UGC - NET: Commerce (08) Paper II (3) UGC - NET: Commerce (08) Paper III (14) ugcnet solved question papers (23) Variance Analysis Notes (1)