CSIR NET CHEMISTRY (JUNE - 2015)
Previous Year Question Paper with Solution.
21. The biological function of carbonic anhydrase and carboxypeptidase A, respectively, are
(a) Interconversion of CO2 and carbonates, and hydrolysis of peptide bond
(b) gene regulation and interconversion of CO2 and carbonates
(c) gene regulation and hydrolysis of peptide bond
(d) interconversion of CO2 and carbonates and gene regulation
Ans. a
Sol. The carbonic anhydrase enzyme that catalyst the rapid interconversion of carbon – di – oxide and water to bicarbonate and protons (and vice versa).
Where, = Arg, Lys, and Ornithine
Correct option is (a)
22. The Fe–Nporphyrin bond distances in the deoxy and oxy-hemoglobin, respectively, are
(a) ~2.1 and 2.0 Å
(b) ~2.0 and 2.0 Å
(c) ~2.2 and 2.3 Å
(d) ~2.3 and 2.5 Å
Ans. a
Sol. 
Correct option is (a)
23. The binding modes of NO in 18 electron compounds [Co(CO)3(NO)] and 
respectively, are
(a) Linear and bent
(b) bent and linear
(c) linear and linear
(d) bent and bent
Ans. c
Sol. 
In both complexes NO donating three electron. So, NO is in linear form.
Note: When NO in bent form donating 1 electron.
Correct option is (c)
24. The role of copper salt as co-catalyst in Wacker process is
(a) oxidation of Pd(0) by Cu(II)
(b) oxidation of Pd(0) by Cu(I)
(c) oxidation of Pd(II) by Cu(I)
(d) oxidation of Pd(II) by Cu(II)
Ans. a
Sol. 
Correct option is (a)
25. For typical Fischer and Schrock carbenes, consider the following statements
(A) Oxidation state of metal is low in Fischer carbene and high in Schrock carbene
(B) Auxilliary ligands are 
in Fischer carbene and non-
in Schrock carbene
(C) Substituents on carbene carbon are non-
in Fischer carbene and 
in Schrock carbene.
(D) Carbene carbon is electrophillic in Fischer carbene and nucleophilic in Schrock carbene
The correct statements are
(a) A, B and C
(b) A, B and D
(c) B, C and D
(d) A, C and D
Ans. b
Sol. Correct option is (b)
26. The species having the strongest gas phase proton affinity among the following,
(a) N3–
(b) NF3
(c) NH3
(d) N(CH3)3
Ans. a
Sol. Gas phase proton affinities
Proton affinity decide the energy release when a molecule/ion accept a proton. Higher the value of gas phase proton affinities more will be basicity. Hence, 
is most basic.
Correct option is (a)
27. Consider the following statements regarding the diffusion current at dropping mercury electrode
A. It does not depend on mercury flow rate
B. It depends on drop time
C. It depends on temperature
Correct statement(s) is/are
(a) A only
(b) B only
(c) A and B
(d) B and C
Ans. d
Sol. According to Ilrovic equation,
(1) So diffusion current depends on mt which is mass flow rate of mercury. So, option (a) is wrong.
(2) Diffusion current also depends on 't' which is drop time.
(3) Though temperature is not directly involved in the equation but changing temperature will change concentration Co as well as mt so idavg also depends on temperature.
28. Q value for the reaction 13N(n, p)13C is 3.236 MeV. The threshold energy (in MeV) for the reaction 13C(p, n)13N is
(a) –3.236
(b) –3.485
(c) 3.485
(d) 3.845
Ans. c
Sol. Threshold energy 
Correct option is (c)
29. The 119Sn NMR chemical shift (approximately in ppm) corresponding to 
(relative to Me4Sn) is
(a) –4
(b) +137
(c) +346
(d) –2200
Ans. d
Sol. Correct option is (d)
30. All forms of phosphorus upon melting, exist as
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. All the allotropic phosphorous forms changes into white P4 discrete units. Which has structure
Correct option is (a)
31. For the oxidation state(s) of sulphur atoms in S2O, consider the following
(A) –2 and +4 (B) 0 and +2 (C) +4 and 0
The correct answer(s) is/are
(a) A and B
(b) A and C
(c) B and C
(d) C only
Ans. a
Sol. The structure of S2O show resonance as
Hence, the probable O.S. of 'S' are (0 and +2) from structure 'I' and (–2 and +4) from structure II.
Correct option is (a)
32. The correct set of pseudohalide anions is
(a) CN–, ClO4–, BF4–, PF6–
(b) 
(c) 
(d) 
Ans. d
Sol. There are many anions which show similar properties like halide ions, they are called pseudo halide and their dimers are called pseudo halogens.
Correct option is (d)
33. In transition metal phosphine (M–PR3) complexes, the back bonding involves donation of electrons from
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. The bonding in phosphine ligands, like that of carbonyls having two components. The primary component is sigma donation of the phosphine lone pair to on empty orbital on the metal. The second component is back donation from filled metal orbital to an empty orbital on the phosphine ligand. This empty phosphorous orbital has been described as being either a d – orbital or an antibonding sigma orbital 
So, in transition metal phosphine (M–PR3) complexes, the back bonding involves donation of electrons from
Correct option is (a)
34. The refluxing of RhCl3.3H2O with an excess of PPh3 in ethanol gives a complex A. Complex A and the valence electron count on rhodium are, respectively
(a) [RhCl(PPh3)3], 16
(b) [RhCl(PPh3)5], 16
(c) [RhCl(PPh3)3], 18
(d) [RhCl(PPh3)5], 18
Ans. a
Sol. The refluxing or RhCl3.3H2O with an excess of PPh3 in boiling ethanol gives a RhCl(PPh3)3– chlorotris (triphenyl phosphien) rhodium (I) is known as wilkinson catalyst.
PPh3 serves as the reducing agent.
It is a square planer 16 – electron complex. Valence electron counting on rhodium metal centre.
(i) there is no overall charge on complex
(ii) there is one anionic ligand (Cl–)
(iii) Rh metal atom must have +1 charge to compensate for the one negatively charged ligand.
So, the oxidation state of Rh is +1.
Now, we can do our electron counting.
Correct option is (a)
35. The 
elimination will be facile in
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. 
Since, C–H, 
bond pair electron donate to the metal for this elimination. Therefore, as the donor ability of the 
– electron pair increases rate of 
– elimination increases.
Electron donor ability at 
bond is
So, more facile 
– elimination occur in option (a)
Correct option (a)
36. The reaction 
follows a/an
(a) Interchange dissociative (Id) mechanism
(b) Dissociative (D) mechanism
(c) Associative (A) mechanism
(d) Interchange Associative (Ia) mechanism
Ans. *
Sol. Correct option is (*)
37. Correct statement on the effect of addition of aq. HCl on the equilibrium is
(a) Equilibrium will shift towards right in case of both A and B
(b) Equilibrium will shift towards left in case of both A and B
(c) Equilibrium will shift towards right in A and left in case of B
(d) Equilibrium will shift towards right in B and left in case of A.
Ans. a
Sol. In first, examples in an esterification in forward direction and an ester hydrolysis in the backward direction. Ester hydrolysis is catalysed by acid or base but esterfication by acid only.
The equilibrium will shift towards right in HCl.
In second example is cyanohydrin formation from a ketone. In HCl solution (at pH less than 12). The oxyanion will be protonated and the reaction drivenover to the right.
Correct option is (a)
38. The compound that exhibits sharp bands at 3300 and 2150 cm–1 in the IR spectrum is
(a) 1-butyne
(b) 2-butyne
(c) butyronitrile
(d) butylamine
Ans. a
Sol. 
Correct option is (a)
39. The 1H NMR spectrum of a dilute solution of a mixture of acetone and dichloromethane in CDCl3 exhibits two singlet of 1 : 1 intensity. Molar ratio of acetone to dicholromethane in the solution is
(a) 3 : 1
(b) 1 : 3
(c) 1 : 1
(d) 1 : 2
Ans. b
Sol. 
Both acetone and CH2Cl2 have equal intensity (1:1) for equalization. Dichorlomethane multiply by (3)
6 × 1 = 6 2 × 3 = 6
Ratio = 1 : 3
Correct option is (b)
40. Intense band generally observed for a carbonyl group in the IR spectrum is due to
(a) The force constant of CO bond is large
(b) The force constant of CO bond is small
(c) There is no change in dipole moment for CO bond stretching
(d) The dipole moment change due to CO bond stretching is large.
Ans. d
Sol. Intensity in IR spectrum is due to charge polarity and change in dipole moment and expressed in term of transition moment between two levels.
Transition moment, 
(transition moment in the form of dipole moment)
Intensity, 
(intensity in the form of dipole moment)
Correct option is (d)
41. The compound that gives precipitate on warming with aqueous AgNO3 is
(a) 
(b) 
(c) 
(d) 
Ans. c
Sol. Those compound gives precipitate on warning with aqueous AgNO3. Which is more stable
Correct option is (c)
42. Following reaction goes through
(a) free radical intermediate
(b) carbanion intermediate
(c) carbocation intermediate
(d) carbene intermediate
Ans. a
Sol. A free radical has been generated at bridgehead position via the Hunsdieker reaction to show that a free radical need not be planar.
Correct option is (a)
43. The most stable conformation for the following compound is
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. The most stable conformation for the following compound is
(B) is less stable due to the presence of Eclipsing interaction between allylic substituent result in allylic 1, 3 strain.
Correct option is (a)
44. The major product formed in the following reaction is
(a) 
(b) 
(c) 
(d) 
Ans. d
Sol. 
Correct option is (d)
45. The correct relation between the following compounds is
(a) enantiomers
(b) diastereomers
(c) homomers (identical)
(d) constitutional isomers
Ans. c
Sol. 
So, these two molecule are homomers (identical)
Correct option is (c)
46. The correct order of heat of hydrogenation for the following compounds is
(a) I > II > III > IV
(b) I > III > II > IV
(c) IV > I > III > II
(d) IV > II > I > III
Ans. b
Sol. Trans alkene is more stable than cis alkene. More the number of 
– hydrogen, lesser will be heat of hydrogenation.
Correct option is (b)
47. Among the following, the correct statement(s) about ribose is (are)
(A) on reduction with NaBH4 it gives optically inactive product.
(B) on reaction with methanolic HCl it gives a furanoside
(C) on reaction with Br2–CaCO3–water it gives optically inactive product.
(D) it gives positive Tollen's test
(a) A, B and D
(b) A, B and C
(c) B and C
(d) D only
Ans. a
Sol. 
Yes, ribose gives positive Tollen's test.
Correct option is (a)
48. Biogenetic precursors for the natural product umbelliferone among the following are
(a) L-tryptophan
(b) cinnamic acid
(c) L-methionine
(d) L-phenylalanine
Ans. b
Sol. Umbelliferone is a phenylpso and as such is synthesized form L – phenylalanine. Which is produced via the Shikimate path way. Phenylalanine is lysated into cinnamic acid. Followed by hydrolyzed 4 – hydroxylate to yield 4 – coumaric acid.
Correct option is (b)
49. Number of signals in the 13C{1H | NMR spectrum of (R)-4-methylpentan-2-ol are
(a) 3
(b) 4
(c) 5
(d) 6
Ans. d
Sol. (R) – 4 – methylpentan – 2 – ol are
So, total number of signal in 13C{1H| NMR spectrum is 6.
Correct option is (d)
50. The major product formed in the following reaction is
(a) 
(b) 
(c) 
(d) 
Ans. d
Sol. 
Correct option is (d)
51. The major product formed in the following reaction is
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. The major product formed in the following reaction is
Correct option is (a)
52. The major product formed in the following reaction is
(a) 
(b) 
(c) 
(d) 
Ans. c
Sol. 
Correct option is (c)
53. The magnitude of the stability constants for K+ ion complexes of the following supra-molecular hosts follows the order,
(a) B > A > C
(b) C > A > B
(c) A > B > C
(d) C > B > A
Ans. c
Sol. The crown ether form complex with metal cation of I-st group. This depend upon
(i) size of cavity
(ii) complexation ability
K+ is best filled in crown – 6 and 'N' is good donar than O and S therefore the order of hosts will be A > B > C
Correct option is (c)
54. Antitubercular drug(s) among the following is (are)
(A) Salbutamol (B) Ethambutanol (C) Isoniazid (D) Diazepam
(a) A and B
(b) B and C
(c) C and D
(d) D alone
Ans. b
Sol. (B) Ethanbutanol and (C) isoniazid are the first line drugs, they are active against mycobacterium turbercli.
Correct option is (b)
55. A particle is in a one-dimensional box with a potential V0 inside the box and infinite outside. An energy state corresponding to n = 0 (n : quantum number) is not allowed because
(a) the total energy becomes zero
(b) the average momentum becomes zero
(c) the wave function becomes zero everywhere
(d) the potential 
Ans. c
Sol. If n = 0, then function becomes not acceptable.
Correct option is (c)
56. An eigenstate of energy satisfie H 
In the presence of an extra constant potential V0
(a) 
(b) both En and average kinetic energy will change
(c) 
(d) 
Ans. c
Sol. 
In presence of extra potential function will remain same but correction term will be introduced into energy in accordance with perturbation theory.
Correct option is (c)
57. The intensity of a light beam decreases by 50% when it passes through a sample of 1.0 cm path length. The percentage of transmission of the light passing through the same sample, but of 3.0 cm path lengths, would be
(a) 50.0
(b) 25.0
(c) 16.67
(d) 12.5
Ans. d
Sol. 
Correct option is (d)
58. The electric-dipole allowed transition among the following is
(a) 
(b) 
(c) 
(d) 
Ans. b
Sol. For allowed transition selection rule is
Correct option is (d)
59. The product 
is the two-fold rotation axis around the x-axis and 
is the xy mirror plane) is
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. 
Correct option is (a)
60. The simplest ground state VB wave function of a diatomic molecule like HCl is written as 
where B stands for
(a) 
(b) 
(c) 
(d) 
Ans. b
Sol. HCl is a ionic compound in valency bond theory
Correct option is (b)
61. Heat capacity of a species is independent of temperature if it is
(a) tetratomic
(b) triatomic
(c) diatomic
(d) monatomic
Ans. d
Sol. For a monatomic species only translational degree of motion is occur. No vibrational degree of freedom. So, heat capacity is independent of temperature.
Correct option is (d)
62. In a chemical reaction: 
xenon gas is added at constant volume. The equilibrium
(a) will shift towards the reactant
(b) will shift towards the products
(c) will not change the amount of reactant and products
(d) will increase both reactant and products
Ans. c
Sol. Addition of neutral gas xenon at constant vaolume will increase total pressure. But partial pressure of gases PCl5, PCl3 and Cl2 will remain same.
For example, 
as neither 
is changing nor V so 
will remain same.
So, there will be no effect on equilibrium.
Correct option is (c)
63. The temperature-dependence of a reaction is given by 
The activation energy (Ea) of the reaction is given by
(a) 
(b) 
(c) 
(d) 
Ans. c
Sol. 
Correct option is (c)
64. For a reaction, 
if the rate of consumption of A is 2 × 10–4 mol dm–3 s–1 the rate of formation of Z (in mol dm–3 s–1) will be
(a) 3 × 10–4
(b) 2 × 10–4
(c) 
(d) 
Ans. a
Sol. Rate of formation of 
× rate of consumption of A
Correct option is (a)
65. Dominant contribution to the escaping tendency of a charged particle with uniform concentration in a phase, depends on
(a) chemical potential of that phase
(b) electric potential of the phase
(c) thermal energy of that phase
(d) gravitational potential of that phase
Ans. b
Sol. 
Escaping tendency of charge species more
If the negative electrical potential is an applied to an electrode electrochemical potential is larger then chemical potential. So, it means that tendency of an electron suffering from the electrode is in hence tendency of oxidation reaction is increase if the positive potential is applied then the tendency of electron to escape. It means the reduction of electron is increased.
Correct option is (b)
66. The intrinsic viscosity depends on the molar mass as
The empirical constants K and a are dependent on
(a) solvent only
(b) polymer only
(c) polymer solvent pair
(d) polymer-polymer interaction
Ans. c
Sol. Correct option is (c)
67. The correct 
for the cell reaction involving steps
(a) 
(b) 
(c) 
(d) 
Ans. d
Sol. 
Equation (i) is multiplied by – nF.
Correct option is (d)
68. The lowest energy-state of an atom with electronic configuration ns1np1 has the term symbol
(a) 3P1
(b) 1P1
(c) 3P2
(d) 3P0
Ans. d
Sol. 
L = 1
S = 1 hence, 2S + 1 = 3 3P
For J value, if orbital is less than half filled than
Hence, 3P0
Correct option is (d)
69. Energy of interaction of colloidal particles as a function of distance of separation can be identified as (1) vander Waals (2) double layer (3) vander Waals and double layer. The correct order of interactions in the figure corresponding to curves (a), (b) and (c), respectively is
(a) 1, 2, 3
(b) 2, 3, 1
(c) 3, 1, 2
(d) 1, 3, 2
Ans. b
Sol. The attractive energy due to vander walls interaction is inversely proportional to the sixth power of the interatomic distance r i.e. 
The electrostatic energy of repulsion, Gel is
Correct option is (b)
70. The packing factor (PF) and number of atomic sites per unit cell (N) of an FCC crystal system are
(a) PF = 0.52 and N = 3
(b) PF = 0.74 and N = 3
(c) PF = 0.52 and N = 4
(d) PF = 0.74 and N = 4
Ans. d
Sol. 
Correct option is (d)
71. Differential pulse polarography (DPP) is more sensitive than D.C. Polarography (DCP). Consider following reasons for it
(A) non-faradic current is less in DPP in comparison to DCP
(B) non-faradic current is more in DPP in comparison to DCP
(C) Polarogram of DPP is of different shape than that of DCP
Correct reason(s) is/are
(a) A and C
(b) B and C
(c) B only
(d) A only
Ans. d
Sol. The residual current in case of DCP is non – faradic current which should be minimum to get the accurate result. This problem of non – faradic current is overcome by use of DPP in which non – faradic current is less than DCP. That is why DPP is more sensitive than DCP.
Though the polarograph is different in both cases but it has nothing to do with sensitivity.
Correct option is (d)
72. Considering the following parameters with reference to the fluorescence of a solution:
(A) Molar absorptivity of fluorescent molecule
(B) Intensity of light source used excitation
(C) Dissolved oxygen
The correct answer for the enhancement of fluorescence with the increase in these parameters is/are
(a) A and B
(b) B and C
(c) A and C
(d) C only
Ans. a
Sol. Increase of intensity of light used increases fluorescene as the fluorescene life – time increases. Molar absorptivity increases absorbance which further enhances fluorescene.
Correct option is (a)
73. The geometric cross section of 125Sn (in barn) is nearly
(a) 1.33
(b) 1.53
(c) 1.73
(d) 1.93
Ans. b
Sol. 
Correct option is (b)
74. Match column A (coupling reactions) with column B (reagents)
The correct match is
(a) 1-II, 2-I, 3-IV, 4-III
(b) 1-I, 2-V, 3-III, 4-IV
(c) 1-IV, 2-III, 3-II, 4-I
(d) 1-II, 2-III, 3-IV, 4-V
Ans. a
Sol. For Suzuki coupling boron is required.
For Heck coupling alkene is required
For Sonagasira coupling terminal alkyne is required
For Negeshi coupling organo zinc is required.
Correct option is (a)
75. The oxoacid of phosphorus having P atoms in +4, +3 and +4 oxidation states respectively is
(a) H5P3O10
(b) H5P3O7
(c) H5P3O8
(d) H5P3O9
Ans. c
Sol. The average of oxidation states is 
Correct option is (c)
76. The geometrices of [Br3]+ and [I5]+, respectively are
(a) trigonal and tetrahedral
(b) tetrahedral and trigonal bipyramidal
(c) tetrahedral and tetrahedral
(d) linear and trigonal pyramidal
Ans. b
Sol. 
Correct option is (b)
77. According to Wade's theory the anion [B12H12]2– adopts
(a) closo-structure
(b) arachno-structure
(c) hypo-structure
(d) nido-structure
Ans. a
Sol. 
Therefore, it is closo structure
Correct option is (a)
78. Considering the inert pair effect on lead, the most probable structure of PbR2[R = 2. 6-C6H3(2, 6-Pr2C6H3)2] is
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. Due to IPE ns2 electron – pair become inactive. In Pb
Therefore, the structure must be
Correct option is (a)
79. The reaction of SbCl3 with 3 equivalents of EtMgBr yields compound X. Two equivalents of SbI3 react with one equivalent of X to give Y. In the solid state, Y has a 1D-polymeric structure in which each Sb is in a square pyramidal environment. Compounds X and Y respectively are
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. 
Correct option is (a)
80. Match the complexes given in column I with the electronic transitions (mainly responsible for their colours) listed in column II
The correct answer is
(a) I-A, II-C and III-B
(b) I-D, II-B and III-C
(c) I-A, II-C and III-D
(d) I-A, II-B and III-C
Ans. a
Sol. 
Correct option is (a)
81. The following statements are given regarding the agostic interaction 
observer in [Ir(Ph3P)3Cl].
(A) Upfield shift of C–H proton in 1H NMR spectrum
(B) Increased acid character of C–H
(C) 
in IR spectrum shifts to higher wavenumber
The correct answer is/are
(a) A and C
(b) B and C
(c) A and B
(d) C only
Ans. c
Sol. 
Due to this agostic interaction C–H bond becomes weak and hydrogen flanked in between M and C. As proton come in contact with metal becomes shielded and upfiled shift in 1H NMR. Since 
bond strength of C–H bond decreases, in IR spectrum shift to lower wave number.
Correct option is (c)
82. Amongst the following 
and (D) 
the compounds with most shielded and deshielded Cp protons respectively, are
(a) D and A
(b) D and B
(c) C and A
(d) C and B
Ans. a
Sol. Here, Cp is cyclopentadienyl ligand is one of the most common and popular ligands in organometllic chemistry.
It is an anionic ligand that normally coordinates in an n5 mode as a 6 electron donor.
Now, 18 – electron rule apply on the complexes
does not follow 18 – electron rule. So, this complex is most deshielded compound when we going 3d to 4d and 4d to 5d series in the transition element the shielding effect decrease because of the electron density or the distance between metal to ligand, increases. So, 
is more shielded than other.
Thus, the compound D is most shielded and compound A is most deshielded.
Correct option is (a)
83. The total of vertices in metal clusters 
are 6, 5 and 5 respectively. The predicted structure of these complexes, respectively are
(a) closo, nido and nido
(b) closo, nido and arachno
(c) arachno, closo and nido
(d) arachno, nido and closo
Ans. b
Sol. 
Correct option is (b)
84. Among the complexes, 
Jahn-Teller distortion is expected in
(a) A, B and C
(b) B, C and D
(c) A and D
(d) B and C
Ans. c
Sol. 
For a compound to show John Teller Distortion eg or t2g set should be electronically degenerate.
Electronically degenerate hence show John Teller Distortion.
Electronically non-degenerate hence, no Jahn-Teller Distortion.
Same as above hence, no Jahn-Teller Distrotion.
Hence, complex will show Jahn–Teller Distortion.
Correct option is (c)
85. The reductive elimination of Ar-R (coupled product) from A is facile when
(a) R = CH3
(b) R = CH2Ph
(c) R = CH2COPh
(d) R = CH2CF3
Ans. a
Sol. 
For reductive elimination, the eliminating group should be electrons releasing group and also the eliminating product should be neutral.
So, only Me group is electron releasing group among all the given option.
Correct option is (a)
86. The total number of metal ions and the number of coordinated imidazole units of histidine in the active site of oxy-hemocyanin, respectively are
(a) 2Cu2+ and 6
(b) 2Fe2+ and 5
(c) 2Cu+ and 6
(d) Fe2+ and 3
Ans. a
Sol. Oxy–hemocyanin are proteins that transport oxygen throughout the bodies of some invertebrate animals. These metalloprotein contain two copper atoms that reversibly bind a single oxygen molecule (O2).
The total of six coordinated imidazole units of histidine present in the active site of oxy - hemocyanine.
Correct option is (a)
87. Match the action of H2O2 in aqueous medium given in column A with the oxidation/reduction listed in column B
The correct answer is
(a) I-A, II-B, III-C, IV-D
(b) I-B, II-D, III-C, IV-A
(c) I-C, II-D, III-B, IV-A
(d) I-D, II-A, III-C, IV-B
Ans. b
Sol. 
Correct option is (b)
88. The reduced form of a metal ion M in a complex is NMR active. ON oxidation, the complex gives an EPR signal with 
Mossbauer spectroscopy cannot characteristic the metal complex. The M is
(a) Zn
(b) Sn
(c) Cu
(d) Fe
Ans. c
Sol. Correct option is (c)
89. The least probable product from A on reductive elimination is
(a) 
(b) CH4
(c) 
(d) 
Ans. c
Sol. 
All the product is possible but possibility (4) is least probable.
Correct option is (c)
90. Water plays different roles in the following reactions.
The correct role of water in each reaction, is
(a) (i) oxidant (ii) acid (iii) base and (iv) reductant
(b) (i) oxidant (ii) base (iii) acid and (iv) reductant
(c) (i) acid (ii) oxidant (iii) reductant and (iv) base
(d) (i) base (ii) reductant (iii) oxidant and (iv) base
Ans. a
Sol. 
Correct option is (a)
91. With respect to 
and 
bonding in 
in the structure given below, which of the following represent the correct bonding.
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. 
At high temperature high spin and at low temperature low spin behaviour at 250 K.
Correct option is (a)
92. The complex 
(phen = 1, 10 – phenanthroline) shows spin cross-over behaviour CFSE and 
at 250 and 150K, respectively are
(a) 
(b) 
(c) 
(d) 
93. Consider the following statements with respect to uranium
(A) 
disproportionates more easily than 
(B) 
is its most stable oxide of U
(C) Coordination number of U in 
is six.
(D) 
is linear
The correct set of statements is
(a) A, B and D
(b) A, C and D
(c) B, C and D
(d) A, B and C
Ans. a
Sol. 
co – ordination number = 8
• U3O8 is stable at high temperature
Correct option is (a)
94. 
For the above conversion, which of the following statements are correct?
(A) CO2 combines with Ni(PR3)2 (1, 5-cyclooctadiene)
(B) Insertion of CO2 occurs
(C) Insertion of 
takes place
The correct answer is
(a) A and B
(b) B and C
(c) C and A
(d) A, B and C
Ans. b
Sol. 
The preparation of tetraethyl pyrone via [2 + 2 + 2] cycloaddition of dynes and CO2. The reaction employs catalytic amounts of Ni(0), PR3 ligand, CO2 (1 atm).
Correct option is (b)
95. Consider the following statements for (NH4)2 [Ce(NO3)6](Z)
(A) Coordination number of Ce is 12
(B) Z is paramagnetic
(C) Z is an oxidising agent
(D) Reaction of Ph3PO with Z gives a complex having coordination number 10 for Ce.
The correct statements are
(a) A, B and C
(b) B, A and D
(c) B, C and D
(d) A, C and D
Ans. d
Sol. 
(1) 
behaves as bidentate ligand. Hence, C. N = 12
(2) Ce4+ has no unpaired electron hence dimagnetic not paramagnetic.
(3) Ce4+ has higher oxidation state hence behave as oxidising agent.
(4) 
Correct option is (d)
96. The major product formed in the following reaction sequence is
(a) 
(b) 
(c) 
(d) 
Ans. c
Sol. 
Correct option is (c)
97. The major products A and B in the following reaction sequence are
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. 
Correct option is (a)
98. The major product formed in the following reaction is
(a) 
(b) 
(c) 
(d) 
Ans. c
Sol. 
Correct option is (c)
99. The major products A and B in the reaction sequence are
(a) 
(b) 
(c) 
(d) 
Ans. c
Sol. 
Correct option is (c)
100. The major products formed in the following reaction are
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. 
Correct option is (a)
101. The correct statement about the following reaction is
(a) The product is 2-fluoropyridin-3-amine and reaction involves nitrene intermediate
(b) The product is 2-fluoropyridin-3-amine and reaction involves radical intermediate
(c) The product is 2-hydroxynicotinamide and reaction involves benzyne-like intermediate
(d) The product is 2-hydroxynicotinamide and reaction involves addition-elimination mechanism.
Ans. a
Sol. Hofmann rearrangement
Correct option is (a)
102. The major product formed in the following reaction is
(a) 
(b) 
(c) 
(d) 
Ans. b
Sol. 
Correct option is (b)
103. The major products A and B formed in the following reactions are
(a) 
(b) 
(c) 
(d) 
Ans. b
Sol. 
Correct option is (b)
104. The major products A and B formed in the following reactions are
(a) 
(b) 
(c) 
(d) 
Ans. d
Sol. 
Correct option is (d)
105. An organic compounds shows following spectral data:
IR(cm–1) : 1680
13C NMR (CDCl3) : 
190, 144, 134, 132, 128, 28 m/z (EI) : 126 (M+, 100%), 128 (M+ + 2, 4.9%)
The structure of the compound is
(a) 
(b) 
(c) 
(d) 
Ans. d
Sol. 
Correct option is (d)
106. The correct set of reagents to effect the following transformation is
(a) (I) (i) NaOMe, MeI; (ii) NaCl, wet DMSO, 160ºC; (II) (i) LDA, –78ºC, TMSCl; (ii) t-BuCl, TiCl4, 50ºC
(b) (I) (i) NaOMe, MeI; (ii) aq. NaOH then HCl, heat; (II) (i) Et3N, TMSCl, rt; (ii) t-BuCl, TiCl4, 50ºC
(c) (i) LDA, t-BuCl (ii) LDA, MeI; (iii) aq. NaOH then HCl, heat
(d) (I) (i) NaCl, wet DMSO, 160ºC; (ii) NaH, t-BuCl; (II) (i) morpholine, H+; (ii) MeI then H3O+
Ans. a
Sol. 
Correct option is (a)
107. The correct structures of the intermediate [A] and [B] in the following reactions are
(a) 
(b) 
(c) 
(d) 
Ans. c
Sol. 
Correct option is (d)
108. The correct reagent combination A and the major product B in the following reaction sequence are
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. 
Correct option is (a)
109. The major product of the following reaction sequence is
(a) 
(b) 
(c) 
(d) 
Ans. d
Sol. 
Correct option is (d)
110. The major product formed in the following reaction is
(a) 
(b) 
(c) 
(d) 
Ans. c
Sol. 
This above two steps are taken from "Total synthesis of Azadiractin".
Correct option is (c)
111. The major products A and B in the following synthetic sequence are
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. 
Correct option is (a)
112. The major product formed in the following reaction is
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. 
Correct option is (a)
113. The hydrocarbon among the following having conformationally locked chair-boat chair form is
(a) 
(b) 
(c) 
(d) 
Ans. d
Sol. 
Correct option is (d)
114. The major product formed in the following reaction sequence is
(a) 
(b) 
(c) 
(d) 
Ans. c
Sol. 
Correct option is (c)
115. The major product in the following reaction sequence is
(a) 
(b) 
(c) 
(d) 
Ans. d
Sol. 
Correct option is (d)
116. Structure of A and B in the following synthetic sequence are
(a) 
(b) 
(c) 
(d) 
Ans. b
Sol. 
Correct option is (b)
117. In the following reaction, the ratio of A : B : C is (*indicates labelled carbon)
(a) 1 : 1 : 1
(b) 1 : 2 : 1
(c) 2 : 1 : 1
(d) 3 : 2 : 1
Ans. c
Sol. 
Correct option is (c)
118. Structure of the major product in the following synthetic sequence is
(a) 
(b) 
(c) 
(d) 
Ans. a
Sol. 
Correct option is (a)
119. Major product formed in the following synthetic sequence on the monoterpene pulegone is
(a) 
(b) 
(c) 
(d) 
Ans. b
Sol. 
Correct option is (b)
120. Optically pure isomers A and B were heated with NaN3 in DMF. The correct statement from the following is
(a) A gives optially pure D and B gives optically pure C
(b) A gives racemic mixture of C and B gives optically pure C
(c) A gives optically pure C and B gives racemic C
(d) A gives optically pure D and B gives racemic D
Ans. b
Sol. A gives racemic mixture of C and B gives optically pure C.
Correct option is (b)
121. A molecular orbital of a diatomic molecule changes sign when it is rotated by 180º around the molecular axis. This orbital is
(a) 
(b) 
(c) 
(d) 
Ans. b
Sol. 
Correct option is (b)
122. IR active normal modes of methane belong to the irreducible representation
(a) E + A1
(b) E + A2
(c) T1
(d) T2
Ans. d
Sol. 
IRR = A1 + E + T1 + 3T2
Translation = T2
Rotational = T1
Therefore, normal modes of vibration = A1 + E + 2T2.
Now, IR active modes = T2
Correct option is (d)
123. The symmetric rotor among the following is
(a) CH4
(b) CH3Cl
(c) CH2Cl2
(d) CCl4
Ans. b
Sol. Symmetric rotor is CH3Cl
The moment of inertia about of C–Cl bond axis is now not negligible because it involves the rotation of three comparatively massive hydrogen atoms offs this axis such a molecule spinning about this axis can be imagined as a top and called symmetric top.
Correct option is (b)
124. The nuclear g-factor of 1H and 14N are 5.6 and 0.40 respectively. If the magnetic field in an NMR spectrometer is set such that the proton resonates at 700 MHz, the 14N nucleus would resonate at
(a) 1750 MHz
(b) 700 MHz
(c) 125 MHz
(d) 50 MHz
Ans. d
Sol. 
Correct option is (d)
125. The spectroscopic technique, by which the ground state dissociation energies of diatomic molecules can be estimates, is
(a) microwave spectroscopy
(b) infrared spectroscopy
(c) UV-visible absorption spectroscopy
(d) X-ray spectroscopy
Ans. b
Sol. The ground state energies of the atomic molecule can be estimated by infrared spectroscopy.
Correct option is (b)
126. The term symbol for the first excited state of Be with the electronic configuration 1s2 2s1 3s1 is
(a) 3S1
(b) 3S0
(c) 1S0
(d) 2S1/2
Ans. a
Sol. 
Correct option is (a)
127. Which of the following statement is INCORRECT?
(a) A Slater determinant is an antisymmetrized wavefunction
(b) Electronic wavefunction should be represented by Slater determinants
(c) A Slater determinant always corresponds to a particular spin state
(d) A Slater determinant obeys the Pauli exclusion principle
Ans. c
Sol. In quantum mechanics, a slater determinant is an expression that describe the wave function of a multifermionic system that satisfies antisymmetry requirements and consequantly the Pauli principle by changing sign upon exchange of two electrons. Slater determinants is a means of ensuring the antisymmetry of a wave function through the use of matrices. A Slater determinant always corresponds to a particular spin state is not true.
Correct option is (c)
128. Compare the difference of energies of the first excited and ground states of a particle confined in (i) a 1-D box 
(ii) a 2-d square box 
and (iii) a 3-d cubic box 
Assume the length of each of the boxes is the same. The correct relation between the energy differences 
for the three states is
(a) 
(b) 
(c) 
(d) 
Ans. b
Sol. 
Correct option is (b)
129. The correct statement about both the average value of position 
and momentum 
of a 1-d harmonic oscillator wavefunction is
(a) 
(b) 
(c) 
(d) 
Ans. c
Sol. One dimensional simple harmonic oscillator
Correct option is (c)
130. The value of the commutator [x, [x, px]] is
(a) 
(b) 
(c) 
(d) 0
Ans. d
Sol. 
Correct option is (d)
131. The equilibrium constants for the reactions 
and 
are K1 and K2 respectively. The equilibrium constant for the reaction 
is
(a) 
(b) 
(c) K1 / K2
(d) K2 – K1
Ans. c
Sol. 
Correct option is (c)
132. Consider the progress of a system along the path shown in the figure 
for one mole of an ideal gas is then given by
(a) 
(b) 
(c) 
(d) 
Ans. *
Sol. Correct option is (*)
133. A thermodynamic equation that relates the chemical potential to the composition of a mixture is known as
(a) Gibb's Helmholtz equation
(b) Gibbs-Duhem equation
(c) Joule-Thomson equation
(d) Debye-Huckel equation
Ans. b
Sol. For a multicomponent open system, we have
Differentiating the above equation, we get
But, by the fundamental equation,
Substracting the two equations, we get
Correct option is (b)
134. According to transition state theory, the temperature-dependence of pre-exponential factor (A) for a reaction between a linear and a non-linear molecule, that forms products through a non-linear transition state, is given by
(a) T
(b) T2
(c) T–2
(d) T–1.5
Ans. d
Sol. 
Correct option is (d)
135. For a given ionic strength, (I) rate of reaction is given by
Which of the following reactions follows the above equation?
(a) 
(b) 
(c) 
(d) 
Ans. b
Sol. 
Correct option is (b)
136. For a reaction on a surface
At low pressure of H2, the rate is proportional to
(a) [H2]
(b) 1/[H2]
(c) [H2]1/2
(d) 1/[H2]1/2
Ans. c
Sol. 
Correct option is (c)
137. The temperature-dependence of an electrochemical cell potential is
(a) 
(b) 
(c) 
(d) 
Ans. c
Sol. 
Correct option is (c)
138. The single-particle partition function (f) for a certain system has the form f = A VeBT. The average energy per particle will then be (k is the Boltzmann constant)
(a) BkT
(b) BkT2
(c) kT / B
(d) kT / B2
Ans. b
Sol. 
From equation (2), average energy per particle 
Correct option is (b)
139. The indistinguishability correction in the Boltzmann formulation is incorporated in the following way: (N = total number of particles, f = single-particle partition function)
(a) replace by F/N!
(b) replace fN by fN/N!
(c) replace f by f/ln(N!)
(d) replace by fN by fN/ln(N!)
Ans. b
Sol. Since Boltzmann formulation deals with whole system containing N number of particles
Therefore, fN should be replaced by 
{Since on incorporating condition of indistinguishability total number of arrangements change by 
Correct option is (b)
140. In a photochemical reaction, radicals are formed according to the equation
If I is the intensity of light absorbed, the rate of the overall reaction is proportional to
(a) I
(b) I1/2
(c) I[C4H10]
(d) I1/2[C4H10]1/2
Ans. a
Sol. 
Therefore, from equation (1).
Correct option is (a)
141. Conductometric titration of a strong acid with a strong alkali (MOH) shows linear fall of conductance up to neutralization point because of
(a) formation of water
(b) increase in alkali concentration
(c) faster moving H+ being replaced by slower moving M+
(d) neutralization of acid.
Ans. c
Sol. When a strong alkali e.g. sodium hydroxide is added to a solution of a strong acid, e.g. hydrochloric acid, the reaction.
During the reaction highly conducting H+ are replaced by M+ which has much lower conductance, so addition of alkali to acid solution is accompanied by a decreases of conductance.
When neutralisation is complete then the further addition of alkali results in an increase of conductance, since the sodium ion and hydroxyl ion are no longer used up in the chemical reaction.
At the neutral point the conductance of the system will have a minimum value.
Correct option is (c)
142. Find the probability of the link in polymers where average values of links are (A) 10, (B) 50 and (C) 100
(a) (A) 0.99, (B) 0.98 (C) 0.90
(b) (A) 0.98, (B) 0.90, (C) 0.99
(c) (A) 0.90, (B) 0.98, (C) 0.99
(d) (A) 0.90, (B) 0.99, (C) 0.98
Ans. c
Sol. 
Correct option is (c)
143. The stability of Iyophobic colloid is the consequence of
(a) van der waals attraction among the solute-solvent adducts
(b) Brownian motion of the colloidal particles
(c) insolubility of colloidal particles in solvent
(d) electrostatic repulsion among double-layered colloidal particles
Ans. d
Sol. Lyophobic colloids are thermodynamically unstable but they are kinetically stable does or does not occur depend on the balance of attractive ands repulsive force. For stabilisation to occur, the repulsive forces must dominate.
Correct option is (d)
144. In a conductometric experiment for estimation of acid dissociation constant of acetic acid, the following values were obtained in four sets of measurements.
1.71 × 10–5, 1.77 × 10–5, 1.79 × 10–5 and 1.73 × 105
The standard deviation of the data would be in the range of
(a) 0.010 × 10–5 – 0.019 × 10–5
(b) 0.020 × 10–5 – 0.029 × 10–5
(c) 0.030 × 10–5 – 0.039 × 10–5
(d) 0.040 × 10–5 – 0.049 × 10–5
Ans. c
Sol. Four sets of measurements are 
Therefore, average value (Mean value) 
Standard deviation, 
Which is in range of 
Correct option is (c)
145. Silver crystallizes in face centered cubic structure. The 2nd order diffraction angle of a beam of X-ray 
of (111) plane of the crystal is 30º. Therefore the unit cell length of the crystal would be
(a) a = 3.151 Å
(b) a = 3.273 Å
(c) a = 3.034 Å
(d) a = 3.464 Å
Ans. d
Sol. 
Correct option is (d)