CEB11 83746

MULTIPLE CHOICE QUESTIONS

D.
R S A
[Ans. (B)]
44. Which of the following represents the composition of Carnallite mineral ?
A.
2 2 3 2
K O A O 6SiO l B. KNO
3
C.
2 4 4 2 2
K SO MgSO MgCl 6H O D.
2 2
KCl MgCl 6H O
[Ans. (D)]
45. The solubility of ( )
3 4
2
Ca PO
in water is y moles/litre. Its solubility product is
A. 6y
4
B. 36y
4
C. 64y
5
D. 108y
5
[Ans. (D)]
46. Paracetamol is
A. Methyl salicylate B. Phenyl salicylate
C. N-acetyl p-amino phenol D. Acetyl salicylic acid
[Ans. (C)]
47. Anhydrous ferric chloride is prepared by
A. Dissolving
( )
3
Fe OH in concentrated HCl B. Dissolving
( )
3
Fe OH in dilute HCl
C. Passing dry HCl over heated iron scrap D. Passing dry Cl
2
gas over heated iron scrap
[Ans. (D)]
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48. Which one of the following is s-butyl phenylvinyl methane ?
A. B.
C. D.
[Ans. (C)]
49. Hybridization of C
2
and C
3
of
3 3
H C CH C CH CH = = are
A. Sp, Sp
3
B. Sp
2
, Sp C. Sp
2
, Sp
2
D. Sp, Sp
[Ans. (B)]
50. Which of the following compounds is not formed in iodoform reaction of acetone ?
A.
3 2
CH COCH I B.
2 2
ICH COCH I C.
3 2
CH COCHI D.
3 3
CH COCI
[Ans. (B)]
51. Two aromatic compounds having formula C
7
H
8
O which are easily identifiable by FeCl
3
solution test (violet
colouration) are
A. o -cresol and benzyl alcohol B. m-cresol and
p
-cresol
C. o -cresol and
p
-cresol D. methyl phenyl ether and benzyl alcohol
[Ans. (A)]
52. The ease of dehydrohalogenation of alkyl halide with alcoholic KOH is
A. 3 < 2 < 1 B. 3 > 2 > 1 C. 3 < 2 > 1 D. 3 > 2 < 1
[Ans. (B)]
53. The ease of Nitration of the following three hydrocarbons follows the order
A. II = III
~
~ I B. II > III > I C. III > II > I D. I = III > II
[Ans. (B)]
54. The correct order of decreasing acidity of nitrophenols will be
A. m-Nitrophenol > p-Nitrophenol > o-Nitrophenol B. o-Nitrophenol > m-Nitrophenol > p-Nitrophenol
C. p-Nitrophenol > m-Nitrophenol > o-Nitrophenol D. p-Nitrophenol > o-Nitrophenol > m-Nitrophenol
[Ans. (D)]
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55. Among the alkenes which one produces tertiary butyl alcohol an acid hydration ?
A.
3 2 2
CH CH CH CH = B.
3 3
CH CH CH CH =
C. ( )
3 2
2
CH C CH =
D.
3 2
CH CH CH =
[Ans. (C)]
56. Which of the following compounds has maximum volatility ?
A. B. B. D.
[Ans. (C)]
57. Which one of the following will show optical isomerism ?
A. B. C. D.
[Ans. (B)]
58. The pH of an aqueous solution of CH
3
COONa of concentrated C(M) is given by
A.
a
1 1
7 pK logC
2 2
+ B.
w b
1 1 1
pK pK logC
2 2 2
+ +
C.
w b
1 1 1
pK pK logC
2 2 2
D.
w a
1 1 1
pK pK logC
2 2 2
+ +
[Ans. (D)]
59. The standard reduction potential E for half reactions are
2
Zn Zn Ze
+
= + E = +0.76 V
2
Fe Fe Ze
+
= + E = +0.41 V
The EMF of the cell reaction
2 2
Fe Zn Zn Fe
+ +
+ = + is
A. 0.35 V B. +0.35 V C. +1.17 V D. 1.17 V
[Ans. (B)]
60. If the equilibrium constants of the following equilibria
2 2 3
1
SO O SO
2
+

and
3 2 2
2SO 2SO O +

are given by K
1
and K
2
respectively, which of the following relations is correct ?
A.
2
2
1
1
K
K
| |
=
|
\ .
B.
3
1
2
1
K
K
| |
=
|
\ .
C.
2
1
1
K
K
| |
=
|
\ .
D. ( )
2
2 1
K K =
[Ans. (A)]
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61. The energy of an electron in first Bohr orbit of H-atom is 13.6 eV. The possible energy value of electron in the
excited state of Li
2+
is
A. 122.4 eV B. 30.6 eV C. 30.6 eV D. 13.6 eV
[Ans. (C)]
62. The amount of heat released when 20 ml 0.5 M NaOH is mixed with 100 ml 0.1 M HCl is x kJ. The heat of
neutralization is
A. 100 x kJ/ mol B. 50 x kJ/ mol C. +100 x kJ/ mol D. +50 x kJ/ mol
[Ans. (A)]
63. Which one of the following has the lowest ionization energy?
A. 1s
2
2s
2
2p
6
B. 1s
2
2s
2
2p
6
3s
1
C. 1s
2
2s
2
2p
5
D. 1s
2
2s
2
2p
3
[Ans. (B)]
64. The ozone layer forms naturally by
A. the interaction of CFC with oxygen B. the interaction of UV radiation with oxygen
C. the interaction of IR radiation with oxygen D. the interaction of oxygen and water vapour
[Ans. (B)]
65. 2gm of metal carbonate is neutralized completely by 100ml of 0.1(N) HCl. The equivalent weight of metal
carbonate is
A. 50 B. 100 C. 150 D. 200
[Ans. (D)]
66. Which one of the following is not true at room temperature and pressure?
A. P
4
O
10
is a white solid B. SO
2
is a colourless gas
C. SO
3
is a colourless gas D. NO
2
is a brown gas
[Ans. (C)]
67. An electric current is passed through an aqueous solution of a mixture of alanine (isoelectric point 6.0) glutamic
acid (3.2) and arginine (10.7) buffered at pH 6. What is the fate of the three acids?
A. Glutamic acid migrates to anode at pH 6. Arginine is present as a cation and migrates to the cathode. Alanine
in a dipolar ion remains uniformly distributed in solution
B. Glutamic acid migrates to cathode and others remain uniformly distributed in solution
C. All three remain uniformly distributed in solution
D. All three move to cathode
[Ans. (A)]
68. The representation of the ground state electronic configuration of He by box-diagram as
||
is wrong because
it violates
A. Hysenberg's Uncertainty Principle B. Bohr's Quantization Theory of Angular Momenta
C. Pauli Exclusion Principle D. Hund's Rule
[Ans. (C)]
69. The electronic transitions from n = 2 to n = 1 will produce shortest wavelength in (where n = principal quantum
state)
A. Li
+2
B. He
+
C. H D. H
+
[Ans. (A)]
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70. In the following electron-dot structure, calculate the formal charge from left to right nitrogen atom;
N = N = N
. .
. .
. .
. .
A. 1, 1, +1 B. 1, +1, 1 C. +1, 1, 1 D. +1, 1, +1
[Ans. (B)]
71. If the molecular wt. of Na
2
S
2
O
3
and I
2
are M
1
and M
2
respectively, then what will be the equivalent wt. of
Na
2
S
2
O
3
and I
2
in the following reaction?
2S
2
O
3
2
+ I
2
S
4
O
6
2
+ 2I

A. M
1
, M
2
B. M
1
, M
2
/2 C. 2M
1
, M
2
D. M
1
, 2M
2
[Ans. (B)]
72. A radioactive atom
X
Y
M
emits two o particles and one | particle successively. The number of neutrons in the
nucleus of the product will be
A. X 4 Y B. X Y 5 C. X Y 3 D. X Y 6
[Ans. (B)]
73. An element belongs to Group 15 and third period of the periodic table. Its electronic configuration will be
A. 1s
2
2s
2
2p
3
B. 1s
2
2s
2
2p
4
C. 1s
2
2s
2
2p
6
3s
2
3p
3
D. 1s
2
2s
2
2p
6
3s
2
3p
2
[Ans. (C)]
74. Which one of the following is paramagnetic?
A. N
2
B. NO C. CO D. O
3
[Ans. (B)]
75. Platinum, Palladium and Iridium are called noble metals because
A. Alfred Nobel discovered them B. They are shining lustrous and pleasing to look at
C. They are found in native state D. They are inert towards many common reagents
[Ans. (D)]
76. Which one is not a constituent of nucleic acid?
A. Uracil B. Guanidine C. Phosphoric acid D. Ribose sugar
[Ans. (C)]
77. The sp
3
d
2
hybridization of central atom of a molecule would lead to
A. Square planar geometry B. Tetrahedral geometry
C. Trigonal bipyramidal geometry D. Octahedral geometry
[Ans. (D)]
78. In aqueous solution glucose remains as
A. Only in open chain form B. Only in pyranoze form
C. Only in furanose forms D. In all three forms in equilibrium
[Ans. (D)]
79. Which of the following is used to prepare Cl
2
gas at room temperature from concentrated HCl?
A. MnO
2
B. H
2
S C. KMnO
4
D. Cr
2
O
3
[Ans. (C)]
80. NO
2
is not obtained on heating
A. AgNO
3
B. KNO
3
C. Cu(NO
3
)
2
D. Pb(NO
3
)
2
[Ans. (B)]
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CEB11 83746
DESCRIPTIVE TYPE QUESTIONS
SUBJECT : CHEMISTRY
FULL MARKS : 10
(Each question carries two marks)
1. The bacterial growth follows the rate law,
dN
KN
dt
= where K is a constant and is the number of bacteria cell at
any time. If the population of bacteria (no. of cell) is doubled in 5 minutes, find the time by which the population
will be eight times of the initial one.
Ans.
dN
KN dN KNdt
dt
= =
dN
Kdt
N
=
} }
ln N = Kt + C
at t = 0, N = 1 (initial)
ln N = Kt
Now, ln N
2
= Kt
2
and ln N
1
= kt
1
( )
2
2 1
1
N
ln K t t
N
| |
=
|
\ .
or, ln 2 = K.5
K =
ln2
5
Now,
1
1
8N ln2
ln t
N 5
| |
= A
|
\ .
ln8 5 3ln2 5
t 15
ln2 ln2

A = = =
Time = 15 min.
2. In x ml 0.3(N) HCl, addition of 200 ml distilled water on addition of 100 ml 0.1 (N) NaOH, gives same final acid
strength. Determine x.
Ans. On dilution strength of HCl =
0.3x
(N)
200 x +
On addition of NaOH the strength of solution =
0.3x 100 0.1
x 100

+
(N) (as the base is present in lesser amount)
By the problem,
2 2
0.3x 0.3x 10
or, 0.3x 30x 60x 0.3x 2000 10x
200 x x 100

= + = +
+ +
or, 20x = 2000
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x = 100
x is 100 mL.
3. Compound A treated with NaNH
2
followed by CH
3
CH
2
Br gave compound B. Partial hydrogenation of compound
B produced compound C, which on ozonolysis gave a carbonyl compound D, (C
3
H
6
O). Compound D did not
respond to iodoform test with I
2
/KI and NaOH. Find out the structures of A, B, C & D.
Ans. There can be two alternatives for A as given below :
H C CH C CH H C CH C C Na
mol NaNH mol C H Br
3 2
1
3 2
1
2 2 5

HC CH Na C C Na
mol NaNH mol C H Br

+
2 2
2 2 5
(A)
(A)
H C CH C C C H
3 2 2 5

+
+
(B)
H C CH C CC H C H CH CH C H
Partial hydrogenation
3 2 2 5 2 5 2 5
=
(C)
ozonolysis

No haloformreaction C H CHO
I OH
2
2
2 5
/
(D)
(B)
4. An organic compound with molecular formula C
9
H
10
O forms 2, 4DNP derivative, reduced Tollen's reagent and
undergoes Cannizzaro reaction. On vigorous oxidation it gives a dicarboxylic acid which is used in the preparation
of terylene. Identify the organic compound.
Ans.
Degree of unsaturation of the compound C
9
H
10
O =
( ) ( ) ( ) 9 4 2 10 1 2 1 2 2
1 5
2
+ +
+ =
( ) n v 2
1
2
(

(
+
(

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The compound must be , as it follows all.
5. Deep blue CuSO
4
.5H
2
O is converted to a bluish white salt at 100C. At 250C and 750C it is then transformed to
a white powder and black material respectively. Identify the salts.
Ans.
exposure 100 C 250 C 750 C
4 2 4 2 4 2 4
(Black)
(Pale blue) (bluish white) (white powder)
CuSO .5H O CuSO .3H O CuSO .H O CuSO CuO


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