Unit # 5…….. M.C.Qs on Atomic Structure
1. A compound material which emits faint visible light by absorbing radiant energy is called:
(a)
|
Fluorescent
|
(b)
|
Cathode
|
(c)
|
Anode
|
(d)
|
None of the above
|
2. Cathode rays experiment shows the presence of:
(a)
|
Electrons
|
(b)
|
Protons
|
(c)
|
Neutrons
|
(d)
|
Nucleus
|
3. The e/m ratio of cathode rays (electrons) is:
(a)
|
1.7588x1011C/kg
|
(b)
|
1.7588x108 C/g
|
(c)
|
All of the above
|
(d)
|
None of the above
|
4. The charge on an electron is:
(a)
|
1.6022x10-19 C
|
(b)
|
1.6022x10-18 C
|
(c)
|
1.6022x10-29 C
|
(d)
|
1.6022x10-21 C
|
5. The mass of an electron is:
(a)
|
9.1096x10-19 kg
|
(b)
|
9.1096x10-31 kg
|
(c)
|
9.1096x10-20 kg
|
(d)
|
9.1096x10-30 kg
|
6. Which particle has a mass of 1/1836 times that of hydrogen?
(a)
|
Electrons
|
(b)
|
Protons
|
(c)
|
Neutrons
|
(d)
|
Positron
|
7. Which particle has a mass of 1836 times that of electron?
(a)
|
β-particles
|
(b)
|
Protons
|
(c)
|
Neutrons
|
(d)
|
Positron
|
8. The e/m ratio for positive (anode) rays is ……………..of nature of gas used
(a)
|
Dependent
|
(b)
|
Independent
|
(c)
|
None of the above
|
(d)
|
All of the above
|
9. Which gas has a highest value of e/m ratio?
(a)
|
Hydrogen
|
(b)
|
Helium
|
(c)
|
Nitrogen
|
(d)
|
Oxygen
|
10. The e/m ratio of cathode rays is always ……….. anode rays.
(a)
|
Less than
|
(b)
|
Greater than
|
(c)
|
Equal to
|
(d)
|
None of the above
|
11. The spontaneous emission of nuclear radiations from radioactive elements is called
(a)
|
Radioactivity
|
(b)
|
Fission
|
(c)
|
Cleavage
|
(d)
|
Ionization
|
12. These are helium nuclei with double positive charge and atomic mass of 4 amu
(a)
|
Alpha rays
|
(b)
|
B-rays
|
(c)
|
Gamma rays
|
(d)
|
X-rays
|
13. Alpha rays consist of:
(a)
|
Stream of hydrogen
|
(b)
|
Stream of Helium
|
(c)
|
Stream of electron only
|
(d)
|
Stream of neutron only
|
14. The fast moving electrons like the cathode rays are called
(a)
|
Alpha rays
|
(b)
|
Beta-rays
|
(c)
|
Gamma rays
|
(d)
|
X-rays
|
15. Which rays are electromagnetic radiations traveling with velocity of light?
(a)
|
Alpha rays
|
(b)
|
Beta-rays
|
(c)
|
Gamma rays
|
(d)
|
X-rays
|
16. The wavelength of gamma rays is …………than most of the X-rays:
(a)
|
Shorter
|
(b)
|
Larger
|
(c)
|
Equal
|
(d)
|
All of the above
|
17. Which radioactive rays have greater penetrating power?
(a)
|
Alpha rays
|
(b)
|
Beta-rays
|
(c)
|
Gamma rays
|
(d)
|
None of the above
|
18. Gamma rays are emitted as
(a)
|
Protons
|
(b)
|
Electrons
|
(c)
|
Neutrons
|
(d)
|
Photons
|
19. The phenomenon of emission of radioactive radiations from nuclei of lighter isotopes of a stable element due to bombardment of fast moving sub atomic particles is called
(a)
|
Radioactivity
|
(b)
|
Natural radioactivity
|
(c)
|
Artificial radioactivity
|
(d)
|
Cleavage
|
19. Which order is correct?
(a)
|
Electron<proton<neutron
|
(b)
|
Proton<electron<neutron
|
(c)
|
Neutron<electron<proton
|
(b)
|
Proton<neutron<electron
|
20. Alpha particle consists of:
(a)
|
2 protons and one neutrons
|
(b)
|
2 electrons and 2 neutrons
|
(c)
|
2 protons and 2 neutrons
|
(b)
|
2 protons and 3 neutrons
|
21. The e/m ratio of positive rays is always:
(a)
|
Much smaller than cathode rays.
|
(b)
|
Much greater than cathode rays.
|
(c)
|
Equal to cathode rays
|
(b)
|
Unpredictable
|
22. Photons of red color are:
(a)
|
More energetic than that of violet colour
|
(b)
|
Less energetic than that of violet color
|
(c)
|
Equal energetic than that of violet colour
|
(b)
|
None of the above
|
23. The frequency of X-rays is:
(a)
|
Very small
|
(b)
|
Very high
|
(c)
|
Intermediate
|
(d)
|
All of the above
|
24. Moseley showed that frequency of X-rays is directly proportional to:
(a)
|
Atomic number
|
(b)
|
Mass number
|
(c)
|
Number of neutrons
|
(d)
|
None of the above
|
25. Moseley found that the wavelength of X-rays emitted ……. regularly with increasing atomic no:
(a)
|
increase
|
(b)
|
Decrease
|
(c)
|
Both a and b
|
(d)
|
None of the above
|
26. The energy of photon is directly proportional to
(a)
|
Frequency of light
|
(b)
|
Wavelength
|
(c)
|
All of the above
|
(d)
|
None of the above
|
27. The energy of photon is inversely proportional to
(a)
|
Frequency of light
|
(b)
|
Wavelength
|
(c)
|
Speed of light
|
(d)
|
None of the above
|
28. The spectrum of sun or of incandescent solids (electric light) is:
(a)
|
Line spectrum
|
(b)
|
Continuous spectrum
|
(c)
|
Both a and b
|
(d)
|
None of the above
|
29. Light of a single wavelength is called
(a)
|
Monochromatic
|
(b)
|
Dichromatic
|
(c)
|
Polychromatic
|
(d)
|
All of above
|
30. It is called fingerprint of element
(a)
|
Line spectrum
|
(b)
|
Continuous spectrum
|
(c)
|
Absorption spectrum
|
(d)
|
All of the above
|
31. Violet colour has a wavelength of
(a)
|
4000-4200 A°
|
(b)
|
4200-4600 A°
|
(c)
|
4600-5000 A°
|
(d)
|
None of above
|
32. Indigo color has a wavelength of
(a)
|
6300-7500 A°
|
(b)
|
4600-5100A°
|
(c)
|
4200-4600 A°
|
(d)
|
5100-5800 A°
|
33. Blue color has a wavelength of:
(a)
|
6300-7500 A°
|
(b)
|
6000-6300 A°
|
(c)
|
5800-6000 A°
|
(d)
|
4600-5100 A°
|
34. Green color has a wavelength of
(a)
|
4000-4200 A°
|
(b)
|
4200-4600 A°
|
(c)
|
4600-5100 A°
|
(d)
|
5100-5800 A°
|
35. Yellow color has a wavelength of
(a)
|
5800-6000 A°
|
(b)
|
4000-4200 A°
|
(c)
|
4200-4600 A°
|
(d)
|
4600-5100 A°
|
36. The color with wave length 600-630 nm (6000-6300A0) is:
(a)
|
Red
|
(b)
|
Green
|
(c)
|
Yellow
|
(d)
|
Orange
|
37. 1A is equal to:
(a)
|
10-10 m
|
(b)
|
10-8cm
|
(c)
|
10-1nm or 102 pm
|
(d)
|
All of the above
|
38. 10A° is equal to:
(a)
|
10-9m
|
(b)
|
10-7cm
|
(c)
|
1nm
|
(d)
|
All of the above
|
39. The value of plank’s constant is:
(a)
|
6.625x10-34 J-S
|
(b)
|
6.625x10-32 J-S
|
(c)
|
6.625x10-36 J-S
|
(d)
|
6.625x10-28 J-S
|
40. It is a distance between two successive crest or trough:
(a)
|
Frequency
|
(b)
|
Wavelength
|
(c)
|
Amplitude
|
(d)
|
Wave number
|
41. The no of waves per unit distance is called:
(a)
|
Wave frequency
|
(b)
|
Wavelength
|
(c)
|
Amplitude
|
(d)
|
wave number
|
42. The inverse of wavelength is called:
(a)
|
Wave frequency
|
(b)
|
Time period
|
(c)
|
Amplitude
|
(d)
|
Wave number
|
43. Rutherford’s alpha particle scattering experiment showed for the first time that the atom has:
(a)
|
Electrons
|
(b)
|
Protons
|
(c)
|
Neutrons
|
(d)
|
A nucleus
|
44. An instrument that measures the intensity and frequency of emitted or absorbed photon radiation is called:
(a)
|
Spectrometer
|
(b)
|
Hydrometer
|
(c)
|
Barometer
|
(d)
|
Calorimeter
|
45. The numerical value of Bohr’s radius
(a)
|
5.29x10-11m
|
(b)
|
5.29x10-9 cm
|
(c)
|
0.529A°
|
(d)
|
All of the above
|
46. Bohr’s theory does not explain the spectra of:
(a)
|
Hydrogen
|
(b)
|
Single electron system
|
(c)
|
Multi electron system
|
(d)
|
None of the above
|
47. Lyman series lies in:
(a)
|
Visible region (l = 4000-8000A°).
|
(b)
|
Ultraviolet region (l = 2000-5000A°).
|
(c)
|
Infra red region (l = 9000-10000A°).
|
(d)
|
Far-infra red region (l >10000A°).
|
48. Balmer series lies in
(a)
|
Visible region
|
(b)
|
Ultra violet region
|
(c)
|
Infra red region
|
(d)
|
None of the above
|
49. Paschen series lies in
(a)
|
visible region
|
(b)
|
Ultra violet region
|
(c)
|
infra red region
|
(d)
|
None of the above
|
50. Lyman series is formed when electrons jump from any higher orbit to ……. orbit
(a)
|
1
|
(b)
|
2
|
(c)
|
3
|
(d)
|
4
|
51. Balmer series is formed when electrons jump from any higher orbit to ____orbit
(a)
|
1
|
(b)
|
2
|
(c)
|
3
|
(d)
|
4
|
52. Paschen series is formed when electrons jump from any higher orbit to………..orbit.
(a)
|
1
|
(b)
|
2
|
(c)
|
3
|
(d)
|
4
|
53. Bracket series is formed when electron jumps from any higher orbit to……….orbit
(a)
|
1
|
(b)
|
2
|
(c)
|
3
|
(d)
|
4
|
54. Pfund series is formed when electron jumps from any higher orbit to _____ orbit
(a)
|
1
|
(b)
|
5
|
(c)
|
3
|
(d)
|
4
|
55. This quantum number tells the size of orbit and energy of electron:
(a)
|
n
|
(b)
|
l
|
(c)
|
m
|
(d)
|
ms
|
56. This quantum number shows the shape of an orbital
(a)
|
n
|
(b)
|
l
|
(c)
|
m
|
(d)
|
ms
|
57. This quantum number shows the orientation of an orbit
(a)
|
n
|
(b)
|
l
|
(c)
|
m
|
(d)
|
ms
|
58. This quantum number specifies the spin of electron in an orbit
(a)
|
n
|
(b)
|
l
|
(c)
|
m
|
(d)
|
ms
|
59. Principle quantum number (n) specifies:
(a)
|
Size of orbit
|
(b)
|
Energy of electron
|
(c)
|
Maximum shell capacity
|
(d)
|
All of the above
|
60. For energy level n=3 the no of possible sub-shells are
(a)
|
1
|
(b)
|
3
|
(c)
|
4
|
(d)
|
9
|
61. If the value of l=0 the orbital is spherical in shape and is called
(a)
|
s
|
(b)
|
p
|
(c)
|
d
|
(d)
|
f
|
62. If the value of l=1 the orbital is dumbbell in shape and is called
(a)
|
s
|
(b)
|
p
|
(c)
|
d
|
(d)
|
f
|
63. If the value of l=2 the orbital is called
(a)
|
s
|
(b)
|
p
|
(c)
|
d
|
(d)
|
f
|
64. No two electrons in an atom has same set of quantum no. this is called
(a)
|
Auf-Bau principle
|
(b)
|
Pauli’s principle
|
(c)
|
Uncertainty principle
|
(d)
|
Hund’s rule
|
65. Which of the following principle limits the maximum no of electrons in an orbital of two?
(a)
|
Auf-Bau principle
|
(b)
|
Pauli’s principle
|
(c)
|
(n + l)rule
|
(d)
|
Hund’s rule
|
66. The electrons are added in an orbital in the order of increasing orbital energy. This is called
(a)
|
Auf-Bau principle
|
(b)
|
Pauli’s principle
|
(c)
|
(n + l)rule
|
(d)
|
Hund’s rule
|
67. In degenerate orbital, electrons would tend to go in separate orbital with same spin. This is the statement of:
(a)
|
Auf-Bau principle
|
(b)
|
Pauli’s principle
|
(c)
|
(n + l)rule
|
(d)
|
Hund’s rule
|
68. Which rule violated in the configuration N = 1s2, 2s2 2px2 2py1
(a)
|
Auf-Bau principle
|
(b)
|
Pauli’s principle
|
(c)
|
(n + l)rule
|
(d)
|
Hund’s rule
|
69. When 3d orbital is complete, the newly entering electron goes into
(a)
|
4f
|
(b)
|
4p
|
(c)
|
4s
|
(d)
|
4d
|
70. The inter nuclear distances between two carbon atoms in diamond is 1.54A than the radius of carbon atom would be:
(a)
|
0.77A°
|
(b)
|
0.077A°
|
(c)
|
1.77A°
|
(d)
|
None of the above
|
71. Atomic radii decrease along a period due to:
(a)
|
Increase in nuclear charge
|
(b)
|
decrease in force of attraction on valence electron
|
(c)
|
Decrease in nuclear charge
|
(d)
|
None of the above
|
72. Atomic radii ……….. in a group from top to bottom:
(a)
|
Increase
|
(b)
|
Decrease
|
(c)
|
Remains same
|
(d)
|
None of the above
|
73. Cations are………… in size than their parent atom:
(a)
|
Smaller
|
(b)
|
Larger
|
(c)
|
Remains same
|
(d)
|
None of the above
|
74. Which one is larger in size than its parent atom?
(a)
|
Cl+
|
(b)
|
Cl
|
(c)
|
Cl–
|
(d)
|
None of the above
|
75. Anions are………… in size than its parent atom
(a)
|
Smaller
|
(b)
|
Larger
|
(c)
|
Equal
|
(d)
|
none of the above
|
80. Na+, Mg2+ and Al3+ are called:
(a)
|
Iso-electric ions
|
(b)
|
compound ions
|
(c)
|
Anions
|
(d)
|
none of the above
|
81. Which one is larger in size?
(a)
|
Na+
|
(b)
|
Mg2+
|
(c)
|
Al3+
|
(d)
|
All are equal in size
|
82. The energy required for the removal of least tightly bounded electron from the valence shell of its isolated atom is called
(a)
|
Ionization energy
|
(b)
|
Ionization potential
|
(c)
|
I.P.
|
(d)
|
All of the above
|
83. The 2nd and 3rd I.P. is always ………. than 1st I.P.
(a)
|
Smaller
|
(b)
|
greater
|
(c)
|
Equal
|
(d)
|
Both a and b
|
84. It is easier to remove electron from which one of the following
(a)
|
Na+
|
(b)
|
Mg+
|
(c)
|
Al3+
|
(d)
|
Ca+
|
85. It is difficult to remove electron from which one of the following
(a)
|
Ca
|
(b)
|
Mg
|
(c)
|
Al2+
|
(d)
|
Na
|
86. Bigger size atoms possess:
(a)
|
High I.P.
|
(b)
|
Low I.P.
|
(c)
|
Both a and b
|
(d)
|
None of the above
|
87. I.P. ………………. from top to bottom in a group
(a)
|
Increase
|
(b)
|
Decrease
|
(c)
|
Same
|
(d)
|
None of the above
|
88. I.P. ………… from left to right in a period
(a)
|
Increase
|
(b)
|
Decrease
|
(c)
|
Same
|
(d)
|
None of the above
|
89. The I.P. is inversely proportional to
(a)
|
Nuclear energy
|
(b)
|
Shielding effect
|
(c)
|
Both a and b
|
(d)
|
None of the above
|
90. The energy released when an electron is added in an lowest energy state of a neutral isolated gaseous atom to form an anion is called
(a)
|
Electron affinity
|
(b)
|
Ionization potential
|
(c)
|
Electronegativity
|
(d)
|
Electropositivity
|
91. The formation of a bivalent anion from a univalent anion is always …………:
(a)
|
Exothermic
|
(b)
|
Endothermic
|
(c)
|
both a and b
|
(d)
|
None of the above
|
92. High values of electron affinity shows that element are
(a)
|
Oxidizing agent
|
(b)
|
Reducing agent
|
(c)
|
Electron donor agents
|
(d)
|
None of the above
|
93. The measure of the ability of an atom to attract an electron pair to itself in a chemical bond is called
(a)
|
Electron affinity
|
(b)
|
Ionization potential
|
(c)
|
Electronegativity
|
(d)
|
Electropositivity
|
94. The average ionization energy and electron affinity is called
(a)
|
Electron affinity
|
(b)
|
Ionization potential
|
(c)
|
Electronegativity
|
(d)
|
Electropositivity
|
95. It is the most electronegative element:
(a)
|
F
|
(b)
|
O
|
(c)
|
Cl
|
(d)
|
N
|
96. Cations are ________electronegative than their parent atom
(a)
|
Less
|
(b)
|
More
|
(c)
|
Equal
|
(d)
|
None of the above
|
97. Anions are …………….electronegative than their parent atom
(a)
|
Less
|
(b)
|
More
|
(c)
|
Equal
|
(d)
|
None of the above
|
98. Electronegativity . ……………in a group from top to bottom
(a)
|
Increase
|
(b)
|
Decrease
|
(c)
|
Both a and b
|
(d)
|
None of the above
|
99. Electronegativity . …………… in a period from left to right
(a)
|
Increase
|
(b)
|
Decrease
|
(c)
|
Both a and b
|
(d)
|
None of the above
|
100. If ΔE.N. between two bounded atoms is greater than 1.7 then the bond in between them will be
(a)
|
Covalent
|
(b)
|
Dative
|
(c)
|
Ionic
|
(d)
|
None of the above
|
101. If the ΔE.N. between two bounded atom is less than 1.7, than the bond in between them will be
(a)
|
Covalent
|
(b)
|
Dative
|
(c)
|
Ionic
|
(d)
|
None of the above
|
102. Which one is more polar than other?
(a)
|
HF
|
(b)
|
NH3
|
(c)
|
H2O
|
(d)
|
CH4
|
103. Which one is more electronegative than the other?
(a)
|
Li+
|
(b)
|
F─
|
(c)
|
Cs
|
(d)
|
O2─
|
NOTE: Nitrogen has 0 electron affinities because it has half-filled valence shell which makes it stable thereby reducing the tendency to accept electron.
M.C.Qs on Solution/Concentration ..Unit # 9
1. Solution are the examples of :
| (a) |
Compounds
|
(b)
|
Homogenous mixture
|
(c)
|
Heterogeneous mixture
|
(d)
|
Colloids
|
2. The amount of solute present in a given amount of solvent or solution is called:
| (a) |
Concentration
|
(b)
|
Molarity
|
(c)
|
Molality
|
(d)
|
Normality
|
3. Alloys are the examples of:
| (a) |
Compounds
|
(b)
|
Elements
|
(c)
|
Solutions
|
(d)
|
Colloids
|
4. An alloy is type of…….. solution:
| (a) |
Solid-gas
|
(b)
|
Solid-solid
|
(c)
|
Liquid-liquid
|
(d)
|
Gas-gas
|
5. In which mode of expression does the concentration of solution remains independent of temperature?
| (a) |
% concentration
|
(b)
|
Molarity
|
(c)
|
Molality
|
(d)
|
Normality
|
6. Isotonic solutions must have the same:
| (a) |
Density
|
(b)
|
Normality
|
(c)
|
Volume
|
(d)
|
osmotic pressure
|
7. A solution of known strength or concentration is called:
| (a) |
Standard solution
|
(b)
|
Normal solution
|
(c)
|
Molal solution
|
(d)
|
Suspension
|
8. The number of gram equivalents of solute dissolved per dm3 of solution is called:
| (a) |
Mole fraction
|
(b)
|
Normality
|
(c)
|
Molality
|
(d)
|
% concentration
|
9. The number of moles of solute dissolved per kilogram of solvent is called:
| (a) |
Mole fraction
|
(b)
|
Normality
|
(c)
|
Molality
|
(d)
|
% concentration
|
10. The number of moles of solute dissolved in 1 liter of solution is called:
| (a) |
Molarity
|
(b)
|
Normality
|
(c)
|
Molality
|
(d)
|
% concentration
|
11. A solution which contains 1 mole of solute dissolved in 1000 cm3 of water is designated by:
| (a) |
1M
|
(b)
|
1m
|
(c)
|
1N
|
(d)
|
10%
|
12. A solution which contains 1 mole of NaCl dissolved in 1 kg of water is designated by:
| (a) |
1M NaCl
|
(b)
|
1m NaCl
|
(c)
|
1N NaCl
|
(d)
|
10% NaCl
|
13. A molal solution contains:
| (a) |
1 mole of solute per dm3 of solution
|
(b)
|
1 mole of solute per 1 kg of solvent
|
(c)
|
1 mole oc solute per 1000 cm3 of solution
|
(d)
|
1 mole of solute per half liter of solution
|
14. A molal solution is one that contains one mole of a solute in:
| (a) |
1000 g the solvent
|
(b)
|
One liter of the solvent
|
(c)
|
One liter of the solution
|
(d)
|
22.4 liter of the solution
|
15. 1N H2SO4 solution contains:
| (a) |
98 g/dm3
|
(b)
|
9.8 g/dm3
|
(c)
|
980 g/dm3
|
(d)
|
49 g/dm3
|
16. 1N NaOH solution contains:
| (a) |
4 g/dm3
|
(b)
|
20 g/dm3
|
(c)
|
80 g/dm3
|
(d)
|
40 g/dm3
|
17. The decimolar solution of H2SO4 solution contains:
| (a) |
98 g/dm3
|
(b)
|
9.8 g/dm3
|
(c)
|
980 g/dm3
|
(d)
|
4.9 g/dm3
|
18. The semimolar solution of NaOH contains:
| (a) |
4 g/dm3
|
(b)
|
20 g/dm3
|
(c)
|
40 g/dm3
|
(d)
|
2 g/dm3
|
19. 56 g of KOH is dissolved in 1 liter of water. The solution obtained is said to be:
| (a) |
Molar
|
(b)
|
Semimolar
|
(c)
|
Decimolar
|
(d)
|
decamolar
|
20. The semimolar solution of KOH contains:
| (a) |
56 g/dm3
|
(b)
|
5.6 g/dm3
|
(c)
|
28 g/dm3
|
(d)
|
112 g/dm3
|
21. 5 liters of 0.5M HNO3 solution contains:
| (a) |
2.5 moles
|
(b)
|
3moles
|
(c)
|
3.5 moles
|
(d)
|
4 moles
|
22. 2 liters of 0.25M NaCl solution contains:
| (a) |
29.25g
|
(b)
|
58.5g
|
(c)
|
5.85g
|
(d)
|
585g
|
23. How many gram of Na2CO3 is required to prepare its 0.5M solution of 250ml?
| (a) |
132.5 g
|
(b)
|
0.1325 g
|
(c)
|
1.325 g
|
(d)
|
13.25 g
|
24. The molarity of solution containing 45g of H2C2O4 in 250ml of solution is:
| (a) |
0.25 M
|
(b)
|
2.5 M
|
(c)
|
0.025 M
|
(d)
|
2 M
|
25. A 10M solution stands for:
| (a) |
Normal solution
|
(b)
|
Molar solution
|
(c)
|
Decamolar solution
|
(d)
|
Decimolar solution
|
26. A N/10 solution stands for:
| (a) |
Normal solution
|
(b)
|
Molar solution
|
(c)
|
Seminormal solution
|
(d)
|
Decinormal solution
|
27. A N/2 solution stands for:
| (a) |
Normal solution
|
(b)
|
Molar solution
|
(c)
|
Seminormal solution
|
(d)
|
Decinormal solution
|
28. The molarity of solution that contains 10g of urea in 500 ml of solution is:
| (a) |
0.33 M
|
(b)
|
3.34 M
|
(c)
|
0.033 M
|
(d)
|
2.5 M
|
29. 1m Na2CO3 solution contains ……g of in 1000g of water.
| (a) |
1.06 g
|
(b)
|
10.6 g
|
(c)
|
106 g
|
(d)
|
53 g
|
30. How many gram of NaCl are to be taken to prepare 100 ml of 10% salt solution?
| (a) |
4 g
|
(b)
|
40 g
|
(c)
|
80 g
|
(d)
|
10 g
|
31. How many gram of HCl are in 1000 g of a 10 % solution?
| (a) |
100 g
|
(b)
|
10 g
|
(c)
|
9,8 g
|
(d)
|
98 g
|
32. The sum of the mole fractions of solute and solvent is equal to:
| (a) |
0
|
(b)
|
1
|
(c)
|
2
|
(d)
|
3
|
33. The suspended particles in suspensions are generally of the size:
| (a) |
10nm
|
(b)
|
100nm
|
(c)
|
1200nm
|
(d)
|
1nm
|
34. The size of constituent particles in solution is generally:
(a)
|
1nm
|
(b)
|
10nm
|
(c)
|
1000nm
|
(d)
|
2-1000nm
|
35. The size of dispersed particles in colloids is:
(a)
|
1nm
|
(b)
|
10nm
|
(c)
|
1000nm
|
(d)
|
2-1000nm
|
36. The intermediate type of mixture is :
(a)
|
Solution
|
(b)
|
Suspension
|
(c)
|
Colloids
|
(d)
|
None of the above
|
M.C.Qs on Oxidation Number ....Unit # 10
1. Which one is incorrect regarding oxidation?
(a)
|
It involves addition of oxygen to a substance or removal of hydrogen from a compound.
|
(b)
|
It involves the loss of electron and is always accompanied by an increase in oxidation number.
|
(c)
|
It always occurs at cathode.
|
(d)
|
All of the above.
|
2. Which one is incorrect regarding reduction?
(a)
|
It involves addition of hydrogen to a substance or removal of oxygen from oxides.
|
(b)
|
It involves the gain of electron and is always accompanied by a decrease in oxidation number.
|
(c)
|
It always occurs at anode.
|
(d)
|
All of the above.
|
3. Which one is an example of oxidation reaction?
(a)
|
Cl
|
+
|
e-
| -------->
|
Cl–
| |||||
(b)
|
H2O
| -------->
|
H+
|
+
| ||||||
(c)
|
Ag+
|
+
|
Cl–
| -------->
|
AgCl
| |||||
(d)
|
Al
|
-
|
3e–
| -------->
|
Al3+
|
4. Which one is an example of reduction reaction?
(a)
|
C
|
+
|
O2
| -------->
|
CO2
| |||||
(b)
|
Fe3+
| -------->
|
Fe2+
| |||||||
(c)
|
H2
| -------->
|
2H+
| |||||||
(d)
|
Zn
| -------->
|
Zn2+
|
5. Which one is incorrect regarding oxidizing agent?
(a)
|
It provides nascent oxygen either on decomposition or on reaction with other substance.
|
(b)
|
It acts as electron acceptor.
|
(c)
|
It undergoes decrease in oxidation number.
|
(d)
|
It always oxidizes itself.
|
6. Which one is incorrect regarding reducing agent?
(a)
|
It provides nascent hydrogen either on decomposition or on reaction with other substance.
|
(b)
|
It acts as electron donor.
|
(c)
|
It undergoes an increase in oxidation number.
|
(d)
|
It always reduces itself.
|
7. Which one of the following reactions involves oxidation and reduction?
(a)
|
NaBr
|
+
|
HCl
| ------->
|
NaCl
|
+
|
HBr
| |||
(b)
|
HBr
|
+
|
AgNO3
| ------->
|
AgBr
|
+
|
HNO3
| |||
(c)
|
H2
|
+
|
Br2
| ------->
|
2HBr
| |||||
(d)
|
Na2O
|
+
|
H2SO4
| ------->
|
Na2SO4
|
+
|
2H2O
|
8. Which one of the following is not an oxidation-reduction reaction?
(a)
|
MgO
|
+
|
2HCl
| ------>
|
MgCl2
|
+
|
H2O
| |||
(b)
|
Mg
|
+
|
HCl
| ------>
|
MgCl2
|
+
|
H2
| |||
(c)
|
Cu
|
+
|
4HNO3
| ------>
|
Cu(NO3)2
|
+
|
2H2O
|
+
|
2NO2
| |
(d)
|
Cu
|
+
|
2H2SO4
| ------>
|
CuSO4
|
+
|
2H2O
|
+
|
SO2
|
9. Which one of the following equation does not represent a redox reaction?
(a)
|
Ba2+
|
+
|
SO42–
| ------>
|
BaSO4
| |||||
(b)
|
Br2
|
+
|
2I–
| ------>
|
2Br–
|
+
|
I2
| |||
(c)
|
Cl2
|
+
|
S2–
| ------>
|
S
|
+
|
2Cl–
| |||
(d)
|
Cu2+
|
+
|
Zn
| ------>
|
Cu
|
+
|
Zn2+
|
10. Which one is incorrect regarding oxidation number?
(a)
|
It shows the extent of oxidation or reduction.
|
(b)
|
Free elements have zero oxidation number.
|
(c)
|
It may have fractional value and it may be zero.
|
(d)
|
It is a number without positive or negative sign.
|
11. When oxidation number of a specie increases in a chemical reaction, the specie is said to be:
(a)
|
Oxidized
|
(b)
|
Reduced
|
(c)
|
Electrolyzed
|
(d)
|
Hydrolyzed
|
12. The oxidation number of an element in the free state
(a)
|
0
|
(b)
|
+1
|
(c)
|
+2
|
(d)
|
-1
|
13. The oxidation number of oxygen in a molecule is not -2 when it is bonded to a …… atom.
(a)
|
Ne
|
(b)
|
S
|
(c)
|
Br
|
(d)
|
F
|
14. The oxidation number of oxygen in OF2 is:
(a)
|
+1
|
(b)
|
+2
|
(c)
|
-2
|
(d)
|
-1
|
15. The oxidation number of oxygen in peroxides (e.g. Na2O2, H2O2, BaO2, and SrO2) is:
(a)
|
-1
|
(b)
|
-1
|
(c)
|
- ½
|
(d)
|
+2
|
16. The oxidation number of oxygen in superoxides (e.g. KO2, RbO2, and CsO2) is:
(a)
|
-1
|
(b)
|
-2
|
(c)
|
- ½
|
(d)
|
+2
|
17. The oxidation number of hydrogen is +1 in its compounds except in:
(a)
|
Covalent hydrides
|
(b)
|
H2O
|
(c)
|
Ionic hydrides
|
(d)
|
CH4
|
18. The oxidation number of Pt in K2PtCl6 is:
(a)
|
+2
|
(b)
|
+4
|
(c)
|
+3
|
(d)
|
-4
|
19. The oxidation number of W in WO3 is:
(a)
|
+5
|
(b)
|
+2
|
(c)
|
+3
|
(d)
|
+6
|
20. The oxidation number of Ni in Ni(CO)4 is:
(a)
|
+5
|
(b)
|
+4
|
(c)
|
Zero
|
(d)
|
+3
|
21. The oxidation number of carbon in C12H22O11 is:
(a)
|
+12
|
(b)
|
-12
|
(c)
|
Zero
|
(d)
|
+4
|
22. The oxidation number of chlorine in HClO4 is:
(a)
|
+1
|
(b)
|
+7
|
(c)
|
+5
|
(d)
|
+3
|
23. The oxidation number of S in SO32- is:
(a)
|
-4
|
(b)
|
+4
|
(c)
|
-2
|
(d)
|
+6
|
24. The oxidation number of S in S2O32- is:
(a)
|
+2
|
(b)
|
+4
|
(c)
|
-2
|
(d)
|
+2.5
|
25. In which of the following substances does sulphur exhibits is highest oxidation state?
(a)
|
S8
|
(b)
|
SO2Cl2
|
(c)
|
Na2S4O6
|
(d)
|
Na2S2O3
|
26. When Cl– ions are converted to Cl2, the oxidation number of chlorine increases from:
(a)
|
-1 to +1
|
(b)
|
-1 to zero
|
(c)
|
-1 to -2
|
(d)
|
-1 to +2
|
27. The most common oxidation state of an element is -2. The number of electrons present in its outermost shell is:
(a)
|
4
|
(b)
|
6
|
(c)
|
5
|
(d)
|
2
|
28. Which one of the following formulae contains nitrogen with an oxidation state of +5?
(a)
|
NH4+
|
(b)
|
N2O5
|
(c)
|
NO2
|
(d)
|
N2O
|
29. The electronic configuration of an element is 1s2, 2s2 2p5. In a chemical reaction, it is most likely to
(a)
|
Donate two electrons
|
(b)
|
Gain one electron
|
(c)
|
Donate one electron
|
(d)
|
Gain two electrons
|
30. An atom has 3 electrons in its valence shell. It is most likely to have following oxidation state?
(a)
|
-3
|
(b)
|
-5
|
(c)
|
+2
|
(d)
|
+3
|
31. What is the oxidation number associated of the element with oxygen in each of the following radicals?
(i). CrO42– (ii). ClO41– (iii). PO43– (iv). PbO22–
(a)
|
+6, +7, +5, +2
|
(b)
|
+6, +5, +5, +4
|
(c)
|
+2, +5, +7, +6
|
(d)
|
+5, +6, +2, +7
|
32. What is the oxidation number of Mn in the following compounds?
KMnO4, K2MnO4, MnO2, MnCl2
(a)
|
+7, +6, +4, +2
|
(b)
|
+7, +2, +6, +4
|
(c)
|
+6, +4, +7, +2
|
(d)
|
+7, +4, +6, +4
|
33. What is the oxidation number of Cl in the following compounds?
Cl2O, HOCl, NaClO3, AuCl3, ClF
(a)
|
+1, +1, +5, -1, -1
|
(b)
|
+1, +2, +5, -1, +1
|
(c)
|
+1, -1, +3, -1, +1
|
(d)
|
+3, +1, +5, -1, -1
|
34. In which of the following formulae contains Mn in its highest oxidation state?
(a)
|
MnO2
|
(b)
|
MnO41–
|
(c)
|
MnO42-
|
(d)
|
Mn(OH)3
|
35. In which of the following formulae contains P in its highest oxidation state?
(a)
|
P2O72–
|
(b)
|
P4
|
(c)
|
PO33–
|
(d)
|
PH3
|
36. In which of the following formulae contains C with oxidation state of -2?
(a)
|
CO
|
(b)
|
Al4C3
|
(c)
|
C2H6O
|
(d)
|
HCO31–
|
37. In which of the following formulae contains C with oxidation state of +4?
(a)
|
C6H12O6
|
(b)
|
C6H10O5
|
(c)
|
CO
|
(d)
|
None of them
|
38. In which of the following formulae contains Cr with oxidation state of +3?
(a)
|
K2Cr2O7
|
(b)
|
H2CrO4
|
(c)
|
CrO3
|
(d)
|
None of them
|
39. In which of the following formulae contains O in its highest oxidation state?
(a)
|
Na2O
|
(b)
|
KO2
|
(c)
|
OF2
|
(d)
|
O2F2
|
40. In the reaction; Zn + H2SO4 ¾¾¾¾® ZnSO4 + H2, which element is reduced?
(a)
|
H
|
(b)
|
O
|
(c)
|
Zn
|
(d)
|
S
|
41. In the reaction; 2HBr + H2SO4 ------> SO2 + Br2 + 2H2O, which element is oxidized?
(a)
|
S
|
(b)
|
Br
|
(c)
|
H
|
(d)
|
O
|
42. In the reaction; Zn + I2 ------> ZnI2, which element is oxidized?
M.C.Qs on Electrochemistry ........Unit # 11
(a)
|
Zinc atom
|
(b)
|
Zinc ion
|
(c)
|
Iodine atom
|
(d)
|
Iodide ion
|
1. The splitting of aqueous sodium chloride into its ions is called:
| (a) |
Cleavage
|
(b)
|
Hydrolysis
|
(c)
|
Ionization
|
(d)
|
Hydration
|
2. Ionization is a(an):
| (a) |
Directionless process
|
(b)
|
Irreversible process
|
(c)
|
Reversible process
|
(d)
|
Constant process
|
3. The substance through which current can flow without change in its composition is called:
| (a) |
Conductor
|
(b)
|
Insulator
|
(c)
|
Semi-conductor
|
(d)
|
Electrolyte
|
4. The substance through which electricity can flow in molten state or solution form is called:
(a)
|
Conductor
|
(b)
|
Insulator
|
(c)
|
Semi-conductor
|
(d)
|
Electrolyte
|
5. Which one is not a strong electrolyte?
(a)
|
HCl
|
(b)
|
NaCl
|
(c)
|
CH3COOH
|
(d)
|
KOH
|
6. Which one is a strong electrolyte?
(a)
|
H2SO4
|
(b)
|
NaOH
|
(c)
|
NaCl
|
(d)
|
All of them
|
7. Which one is a weak electrolyte?
(a)
|
H2S solution
|
(b)
|
Ammonia solution
|
(c)
|
CH3COOH
|
(d)
|
All of the above
|
8. Which one of the following is the best conductor of electricity when molten?
(a)
|
(b)
|
Sugar
| |
(c)
|
Lead (II) iodide
|
(d)
|
Paraffin wax
|
9. Which of the following could e added to water to make a solution which is a good conductor of electricity?
(a)
|
Copper
|
(b)
|
Ethanol or acetic acid
|
(c)
|
Caustic soda
|
(d)
|
Calcium carbonate
|
10. What ions are present in aqueous sodium sulphate solution?
(a)
|
Na+, SO42–, H+,
|
(b)
|
Na+, SO42–, H+, O2–
|
(c)
|
Na2+, SO42–, H+, O2–
|
(d)
|
Na2+, SO42–
|
11.The electrical conductivity of an electrolyte depends upon:
(a)
|
Number of ions
|
(b)
|
Degree of dilution
|
(c)
|
Temperature
|
(d)
|
All of the above
|
12. The process in which electric current is used to bring about a non-spontaneous redox reaction is called:
(a)
|
Pyrolysis
|
(b)
|
Hydrolysis
|
(c)
|
Electrolysis
|
(d)
|
Hydration
|
13. A cell in which electric current is used to bring about a non-spontaneous redox reaction is called:
(a)
|
Electrochemical cell
|
(b)
|
Electrolytic cell
|
(c)
|
Galvanic cell
|
(d)
|
Voltaic cell
|
14. A cell in which electric current is produced from a spontaneous redox reaction is called:
(a)
|
Electrochemical cell
|
(b)
|
Electrolytic cell
|
(c)
|
Galvanic cell
|
(d)
|
Voltaic cell
|
15. During electrolysis of 18 g of acidified water, H2 released at cathode at s.t.p. is:
(a)
|
22.4 liter
|
(b)
|
11.2 liter
|
(c)
|
5.6 liter
|
(d)
|
44.8 liter
|
16. Electrolysis of acidified water gives off oxygen at ……. and hydrogen gas at …….respectively.
(a)
|
Cathode, anode
|
(b)
|
Anode, anode
|
(c)
|
Anode, cathode
|
(d)
|
Cathode, cathode
|
17. Which one of the following elements is extracted by electrolysis?
(a)
|
Carbon
|
(b)
|
Sodium
|
(c)
|
Nitrogen
|
(d)
|
Zinc
|
18. Which one of the following elements is not extracted by electrolysis?
(a)
|
Aluminium
|
(b)
|
Magnesium
|
(c)
|
Potassium
|
(d)
|
Copper
|
19. Which type of elements are extracted by electrolysis?
(a)
|
Transition elements
|
(b)
|
Noble gases
|
(c)
|
Representative elements
|
(d)
|
Less reactive el ements
|
20. Which type of elements cannot be extracted by electrolysis?
(a)
|
Transition elements
|
(b)
|
More reactive elements
|
(c)
|
Representative elements
|
(d)
|
All elements can be extracted.
|
21. Electrolysis involves:
(a)
|
Movement of cations and anions of an electrolyte towards their respective electrodes.
|
(b)
|
Electrolytic decomposition of electrolytes.
|
(c)
|
Deposition of ions as neutral species on electrodes in an electrolytic cell.
|
(d)
|
All of the above.
|
22. An electrolytic cell is one which involves:
(a)
|
Conversion of electrical energy into chemical energy.
|
(b)
|
Conversion of chemical energy into electrical energy.
|
(c)
|
Both a and b.
|
(d)
|
None of the above.
|
23. A Galvanic or Voltaic cell is one which involves:
(a)
|
Conversion of electrical energy into chemical energy.
|
(b)
|
Conversion of chemical energy into electrical energy.
|
(c)
|
Both a and b.
|
(d)
|
None of the above.
|
24. Which one of the following is correct regarding cathode?
(a)
|
Cathode is the electrode at which reduction takes place.
|
(b)
|
Cathode is the negative electrode in an electrolytic cell whereas in a Galvanic cell it is the positive electrode.
|
(c)
|
In both electrolytic and Galvanic cells, cations move towards the cathode.
|
(d)
|
All of the above.
|
25. Which one of the following is correct regarding anode?
| (a) |
Anode is the electrode at which oxidation takes place.
|
| (b) |
Anode is the positive electrode in an electrolytic cell whereas in a Galvanic cell it is the negative electrode.
|
| (c) |
In both electrolytic and Galvanic cells, anions move towards the anode.
|
| (d) |
All of the above.
|
26. Which one of the following is correct regarding salt bridge?
| (a) |
Salt bridge is a device that keeps internal continuity between the two half cells of a Galvanic cell by means of an inert salt solution placed in the u-tube.
|
| (b) |
It completes the cell circuit and also maintains the electrical neutrality by diffusion of ions through it.
|
| (c) |
In cell reaction, a salt bridge is represented by two vertical lines[║]
|
| (d) |
All of the above.
|
27. Which particles are responsible for the conduction of electricity through
(i) metals, (ii) electrolytes:
(i) Metals
|
(ii) Electrolytes
| |
(a)
|
Negative ions
|
Positive ions
|
(b)
|
Electrons
|
Electrons
|
(c)
|
Electrons
|
Positive & negative ions
|
(d)
|
Positive ions
|
Positive & negative ions
|
28.Which one of the following correctly describes the process occurring at the electrodes when molten sodium chloride is electrolyzed?
Anode
|
Cathode
| |
(a)
|
Oxidation
|
Reduction
|
(b)
|
Reduction
|
Oxidation
|
(c)
|
Oxidation
|
Oxidation
|
(d)
|
Reduction
|
Reduction
|
29. Which of the following products are given off at the electrodes during the electrolysis of molten magnesium chloride between carbon electrodes?
Anode
|
Cathode
| |
(a)
|
Magnesium
|
Chlorine
|
(b)
|
Oxygen
|
Magnesium
|
(c)
|
Chlorine
|
Hydrogen
|
(d)
|
Chlorine
|
Magnesium
|
30. What are the products of the electrolysis of dilute sulphuric acid using inert electrodes?
Anode
|
Cathode
| |
(a)
|
Hydrogen
|
Oxygen
|
(b)
|
Hydrogen
|
Carbon dioxide
|
(c)
|
|
Oxygen
|
(d)
|
Oxygen
|
Hydrogen
|
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