Chemistry Electro Chemistry Online Mcqs Test

Malik TahirLast Updated: October 14, 2025

Important Electro Chemistry Question and Answer

Total Questions:	192
Time Allowed:	60 Minutes
Total Marks:	192
How to Attempt Test:	Please choose the right Option in MCQ-type question.
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Electro Chemistry Practice Test Online With Explanation

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Page 1 of 8

Chemistry

1. 2.5 faradays of electricity is passed through solution of CuSO₄. The number of gram equivalents of copper deposited on the cathode would be

1.25

1 2

None of these

2.5

2. 0.5 M of H₂SO₄ is diluted from 1 liter to 10 liter, normality of resulting solution is

1 N

0.1N

10 N

11 N

3. Which of the following (IM) conducts more electricity?

Nitric acid

Sulphuric acid

Phosphorus acid

Boric acid

4. Which one of the following will be good conductor of electricity?

Pure distilled water

Dilute solution of glucose

Molten NaCl

Chloroform

5. Molton NaCl conducts electricity due to the presence of

Free ions

Free electrons

Free molecules

Atoms of Na and Cl.

6. Voltaic cell can be recharged by

By heating it

By replacing external circuit with external source of electricity

By removal of solution

By addition of fresh solution

7. If α is the degree of dissociation of Na₂SO₄ the Vant Hoff’s factor (i) used for calculating the molecular mass is

1 – α

1 – 2 α

1 + 2 α

1 + α

8. Half cells are interconnected through

Salt Bridge

Electric circuit

Wire

No connection exists

9. Which of the following is the use of electrolysis?

Both A and B

Electroplating

None of these

Electrorefining

10. Oxidation number of carbon in NaHCO₃ is

-6

11. A dry alkaline cell has porous Zn anode & MnO₂ as cathode the electrolyte used is

KOH

NH₄OH

NaOH

Ca(OH)₂

12. What is the molarity of H₂SO₄ solution that has density of 1.84 gm/cm³ which was at 35°C and contains 98% by weight?

4.18 M

18 M

18.4 M

8.14 M

13. Separation of azeotropic mixture into pure components is carried out by

Fractional distillation

Vacuum distillation

Distillation

None of these

14. A 20% solution of NaCl by weight means that

20g NaCl/100ml

5.58g NaCl/100m

58.5g NaCl/100ml

10.0g NaCl/100ml

15. Wen quantity of electricity passed is one faraday then the mass deposited at the electrode is equal to

Electrochemical equivalent

None of these

One gm. Equivalent weight

One gm. atomic weight

16. Which of the following solution of H₂SO₄ is more concentrated?

1 molar

1 molal

1 normal

All

17. Hydrogen gas is not liberated when the following metal is added to dil. HCI.

18. Which of the following is a strong electrolyte?

Ca(NO₃)₂

HCN

CH₃COOH

NH₄OH

19. The specific conductance of 0.1 M NaCl solution is 1.06 x 10¯² ohm¯¹mol¯¹. Its molar conductance in ohm¯¹ cm² mol¯¹ is

1.06 x 10⁴

1.06 x 10³

1.06 x 10²

20. Maximum freezing point falls in

Water

Camphor

Naphthalene

Benzene

21. Pure water does not conduct electricity because it

Is neutral

Has low boiling point

Is almost unionized

Is readily decomposed

22. The degree of dissociation of weak electrolyte increases as

Dilution decreases

Pressure increases

None

Dilution increases

23. Sea water has 5.65 x 10¯³ g of dissolved oxygen calculate the conclusion of oxygen in sea water in ppx

5.51

1.32

5.65

6.1

24. 96500 C electricity is passed through CuSO₄. The amount of copper precipitated is

0.25 mole

0.5 mole

2.00 mole

1.0 mole

25. A redox reaction involves

Ion combination reaction

A reaction in a solution

Proton transfer

Electron transfer

Page 2 of 8

26. Standard hydrogen electrode has an arbitrarily fixed potential

1.00 volt

0.10 volt

0.00 volt

None of these

27. The osmotic pressure of 1 m solution at 27°C is

2.46 atm

1.21 atm

12.1 atm

24.6 atm

28. If 5.85 g of NaCl are dissolved in 90 g of water, the mole fraction of NaCl is

0.1

0.0196

0.2

0.01

29. Metals usually conduct electricity because

Metals have high resistance

In metals the ions are free to more

Metals are decomposed by current

They are mobile electrons in the metallic structure

30. Stronger the oxidizing agent, greater is the

Redox potential

e.m.f of cell

Oxidation potential

Reduction potential

31. A cell constant is generally found by measuring the conductivity of aqueous solution of

MgCl₂

KCl

NaCl

BaCl₂

32. In an electrolytic cell current flows

From anode to cathode inside the cell

From anode to cathode in an outer circuit

From cathode to anode in outer circuit

From cathode to anode inside the cell

33. Calculate the percentage by weight if NaCl, if 2.0 g of NaCl is dissolved in 20g of water

11.2%

9.09%

14.25%

13.1%

34. It azeotropic mixture showing positive deviation from Rault’s law, the volume of the mixture is

None of these

Equal to the total volume of the components

Slightly more than the total volume of the components

Slightly less than the total volume of the components

35. The amount of electricity that can deposit 108 g of silver from silver nitrate solution is

1 coulomb

1 faraday

1 ampere

2 ampere

36. The cryoscopic constant of water is 1.86. The elevation of B.P for a 0.1m solution of a solute in water is

18.6 c°

1.86 c°

Sufficient date not given

0.186 c°

37. In electrolytic cell, electricity in carried out by

Non-spontaneous reaction

All

Spontaneous reaction

Neutralization

38. Choose the cell among the following list in which conversation of electrical energy into chemical energy takes place

Electrolytic cell

Daniel cell

Galvanic cell

Fuel cell

39. Anode electrode element always have _________ position in electrochemical series

Higher

Not particular

Lower

In middle

40. Oxidation in a chemical reaction involves

Increase in oxidation number

Both are possible

Increase in oxidation number of all the elements on reactant side

Decrease in oxidation number

41. When electricity is passed through molten Al₂O₃ + Na₃AIF₆ and 13.5 gms of Al are deposited, the number of faraday must be

1.5

2.0

1.0

0.5

42. In the conversion of Br2 to BrO₃¯¹ the oxidation state of bromine changes from

0 to –3

1 to 5

2 to 5

0 to 5.

43. In a chemical reaction, oxidation process involves

Increase in oxidation number of element

Decrease in oxidation number of element

Oxidation number neither increases nor decreases

Increase in oxidation number of the elements in reactants

44. A smuggler could not carry gold by chemically depositing iron on the gold surface since

Gold has higher reduction potential then iron

Iron rusts

Gold has lower reduction potential then iron

Gold is denser

45. Reduction always occurs

At anode

At cathode

None of these

Both A and B

46. Electrolysis is the process in which a chemical reaction takes place at the expense of

Chemical energy

Electrical energy

Heat energy

None of these

47. The Vant Hoff factor (i) accounts for

Degree of solubilization of solute

The degree of decomposition of solution

The extent of dissolution of solute

The extent of dissociation of solute

48. The conductivity of strong electrolyte

Does not change on dilution

Depends on density of electrolyte itself.

Increases on dilution slightly

Decreases on dilution

49. The reference electrode is made by using

CuSO₄

Hg₂Cl₂

HgCl₂

ZnCl₂

50. The specific conductance of a 0.1 N KCl solution at 23°C is 0.012 ohm¯¹ cm¯¹. The resistance of cell containing the solution at the same temperature was found to be 55 ohm. The cell constant will be

0.66 cm¯¹

1.12 cm¯¹

0.142 cm¯¹

0.918 cm¯¹

Page 3 of 8

51. Which one of the following is a colligative property?

Surface tension

Viscosity

Osmotic pressure

Refractive index

52. Prevention of corrosion of iron by Zn coating is called

Photo electrolysis

Cathodic protection

Electrolysis

Galvanization

53. Equal volumes of ethylene glycol (molar mass = 62) and water (molar mass = 18) are mixed. The depression in freezing point of water is (given Kf of water 1.86 K mol¯¹ kg and specific gravity of ethylene glycol is 1.11)

0.333

3.33

33.3

0.0033

54. In a Galvanic cell, the electrons flow from

Cathode to anode through the external circuit

Anode to cathode through the external circuit

Cathode to anode through the solution

Anode to cathode through the solution

55. Specific conductivity of a solution

Remains unchanged with dilution

Decreases with dilution

Depends on mass of electrolyte

Increases with dilution

56. Cathode provides electrons to

+Ve ion

Does not provide any electron

Neutral atom

-Ve ion

57. Electricity in voltaic cell is produced due to

Oxidation

Neutralization

Reduction

B + C

58. Salt bridge transfers

Current

Electrons

Ions

Anion

59. In a Galvanic cell

Electrical energy is converted into heat

Chemical energy is converted into electricity

Chemical energy is converted into heat

Electrical energy is converted into chemical energy

60. Strong reducing agents have

Greater positive value of standard reduction potential

Greater negative value of standard reduction potential

Lesser positive value of standard reduction potential

None of these

61. A 0.001 molal solution of [Pt(NH₃)₄Cl₄] in water had a freezing point depression of 0.0054°C. If Kf for water is 1.80, the correct formulation for the above molecule is

[Pt(NH₃)₄Cl₄]

[Pt(NH₃)₄Cl₃]Cl

[Pt(NH₃)₄Cl]Cl₃

[Pt(NH₃)₄Cl₂]Cl₂

62. Standard reduction electrode potential of three metals A, B and C are respectively + 0.05 V, - 3.0 and -1.2V. The reducing power of

C > B > A

B > C > A

A > B > C

A > C > B

63. The electrode with more negative value of reduction potential acts as

None of these

Cathode

Electrode

Anode

64. 96500 C of electricity liberates from CuSO₄ solution

31.75 g of Cu

96500 g of CU

63.5 g of Cu

100 g of Cu

65. The molality of 2% NaCl. W/W solution is approximately

2.05

0.25

0.5

0.05

66. An electric current is passed through silver nitrate solution using silver electrodes. 10.79 g of silver was found to be deposited on the cathode if the same amount of electricity is passed through copper sulphate solution using copper electrodes, the weight of copper deposited on the cathode is

2.3 g

12.8 g

6.4 g

3.2 g

67. Units of molarity are

Mol/lit

Kg/lit

None of these

Gm/lit

68. Camphor is often used in molecular mass determination because

It has a very high cryoscopic constant

It is solvent for organic substances

It is volatile

It is readily available

69. Out of Cu, Ag, Fe and Zn the metal which can displace all others from their salt solutions is

70. The equivalent conductivity of 0.1 M week acid is 100 times less than that at infinite dilution. The degree of dissociation is

100

0.01

0.001

71. Choose the best reducing agent among the following

I¯¹

Cl¯¹

F¯¹

Br¯¹

72. Solution with same osmotic pressures are called

Isotonic

Hypertonic

Hypotonic

Normal

73. When the solute is present in trace quantities the following expression is used?

Microgram percent

Milligram percent

Parts per million

Gram per million

74. In the electrolysis of molten sodium chloride, what is the yellow green gas formed?

Oxygen

Hydrogen

Chlorine

Chloride

75. The pressure at which water boils at 101.5 °c is

2.5 atom

Slightly more than 1 atom

760 mm of Hg

750 torr

Page 4 of 8

76. How many g of dibasic acid (mol. wt. 200) should be present in 100 ml of the aqueous solution to give 0.1 Normality?

1 g

10 g

20 g

2 g

77. The osmotic pressure of a dilute solution is directly proportional to the

Diffusion rate of the solute

Flow of solvent from a concentrated to a dilute solution

Ionic concentration

Elevation in boiling point

78. A solution contains 1.2046 x 10²⁴ hydrochloric acid molecules in one dm³ of the solution. The strength of the solution is

4 N

6 N

8 N

2 N

79. 1.0 g of pure calcium carbonate was found to require 50 ml of dilute HCl for complete reaction. The strength of HCl solution is given by

2 N

0.4 N

0.2 N

4 N

80. Equal volumes of 0.1 M AgNO₃ and 0.2 M NaCl are mixed. The concentration of NO¯₃ ions in the mixture will be

0.2 M

0.1 M

0.15 M

0.05 M

81. A cell in which chemical energy is converted into electrical energy is called

Galvanic cell

Electrolytic cell

Dry cell

Fuel cell

82. The volume of 0.1 M H₂SO₄ required to neutralize completely 40 ml of 0.2 M NaOH solution is

10 ml

40 ml

20 ml

80 ml

83. Which of the statements given below concerning properties of solution, describe a colligaive effect?

Vapour pressure of pure benzene decreases by the addition of naphthalene

Boiling point of pure water decreases by the addition of ethanol

Boiling point of pure benzene increases by the addition of toluene

Vapour pressure of pure water decreases by the addition of nitric acid

84. Secondary cell is

Non rechargeable

Daniel cell

Rechargeable

Electrolytic cell

85. Which of the following will have the highest boiling point at 1 atm pressure?

0.1 M Sucrose

0.1 M BaCl₂

0.1 M Glucose

0.1 M NaCl

86. A certain current liberate 0.5 g of hydrogen in 2 h. How many grams of copper can be liberated by the same current flowing for the same time in a copper sulphate solution?

12.7 gm

15.9 gm

31.8 gm

63.5 gm

87. Density of H₂SO₄ in lead accumulator is

1.2 g/Cm³

1.25g/Cm³

120 g Cm³

1.15 g/Cm³

88. When molten sodium undergoes electrolysis, the ion reduces is

Na⁺

Cl¯

None of these

Both Na⁺ and CI¯

89. In alkaline battery anode is made up of

MnO₂

Cadmium

AgO₂

90. Which of the following element act as inert electrode?

None

91. The weight of pure NaOH required to prepare 250 cm³ of 0.1 N solution is

5 g

2 g

4 g

1 g

92. The relative lowering of vapour pressure is equal to mole fraction of the solute. This law is called:

Henry’s law

Arrhenius law

Ostwald’s law

Raoult’s law

93. The reference calomel electrode is made from which of the following?

ZnCl₂

HgCl₂

Hg₂Cl₂

CuSO₄

94. Which oxide has +2 oxidation number of oxygen?

F₂O

Na₂O₂

Na₂O

Cl₂O

95. If the ionic product of a solution is less than the solubility product, the solution is

Supersaturated

Ideal

Unsaturated

Saturated

96. A current of 9.65 ampere flowing for 10 minutes deposits 3.0 g of the metal which is monovalent. The atomic mass of the metal is

96.5

97. The half-reaction that occurs at the anode during the electrolysis of molten sodium bromide is:

Na⁺ + e– → Na

Na → Na⁺ + e–

2Br– → Br₂ + 2e –

Br₂ + 2e – → 2Br –

98. Chemical used in salt bridge is

KOH

KBr

KNO3

KCI

99. In a solution of CuSO₄ how much time will be required to precipitate 2g copper by 0.5 ampere current?

642 sec

102 sec

12157.48 sec

510 sec

100. The standard e.m.f. of a galvanic cell involving cell reaction with n = 2 is found to be 0.295 V at 25°C. The equilibrium constant of the reaction would be

2.0 x 10¹¹

4.0 x 10¹²

1.0 x 10¹⁰

1.0 x 10²

Page 5 of 8

101. Same amount of electric current is passed through solution if AgNO₃ and HCl. If 1.08 g of silver is obtained in the first case, the amount of hydrogen liberated as S.T.P. in the second case is:

112 cm³

22400 cm³

1.008 g

224 cm³

102. If liquids A and B form an ideal solution

The free energy as well as the entropy of mixing are each zero

The free energy of mixing is zero

The enthalpy of mixing is zero

The entropy of mixing is zero

103. In a hydrogen-oxygen fuel cell, combustion of hydrogen occurs to

Create potential difference between two electrodes

Remove adsorbed oxygen from electrode surfaces

Generate heat

Produce high purity water

104. The depression of freezing point is directly proportional to

Molarity of the solution

Mole fraction of the solution

Molarity of the solvent

Molality of the solution

105. The + 1 oxidation state of P is found in

H₃PO₄

H₃PO₃

H₄P₃O₇

H₃PO₂

106. Which of the substances Na, Hg, S Pt and graphite can be used as electrodes in electrolytic cells having aqueous solution?

Na, Pt and graphite

Pt and graphite only

Na and Hg

Na and S only

107. The standard EMF of Daniel cell is 1.10 volt. The maximum electrical work obtained from the Daniel cell is

212.3 kJ

175.4 kJ

106.15 kJ

53.07 kJ

108. What is the molality of a solution prepared by dissolving 5 g of toluene in 250 g of Benzene.

0.217

3.12

4.10

7.20

109. Mole fraction of pure water is

Slightly greater than one

Slightly less than one

None of these

Exactly equal to one

110. Li occupies higher position in the electrochemical series of metals as compared to Cu since

The standard reduction potential of Cu²+/Cu is lower than that of Li⁺/Li

The standard reduction potential of Li⁺/Li is lower than that of Cu²+/Cu

The standard oxidation potential of Li/Li⁺ is lower than that of CuCu²⁺

Li is smaller in size as compared to Cu

111. When common salt is dissolved in water

B.P of water decrease

Any possibility

B.P of water increase

B.P of water remain constant

112. An aqueous solution of ethanol in water has vapour pressure

Equal to that of water

More than that of H₂O

Less than that of water

Equal to that of ethanol

113. After adding a solute freezing point of solvent decreases to -0.186. Calculate ∆ Tb if Kf = 1.86 and Kb = 0.521

0.0186

0.521

0.0521

1.86

114. Of the following, the metal that cannot be obtained by electrolysis of aqueous solution of their salts are:

115. Vant Hoff’s factor of Ca(NO₃)₂ is

116. The number of moles of a solute in 500 cm³, 3M solution is

1.5

117. 8 g of NaOh is dissolved in 500 cm³ of solution, its molarity is:

0.04 M

0.4 M

0.2 M

0.8 M

118. A device which converts electrical energy into chemical energy is called

An electrolytic cell

A voltaic cell

A galvanic cell

A chemical cell

119. Under the process of rusting of iron, 4Fe + 3O₂ → 2Fe₂O₃, iron is

Reduced

Hydrolyzed

Oxidized

Precipitated

120. Which one of the following substance when dissolved in water give acidic solution

NH₄Cl

NaCl

Na₂SO₄

CH₃ CooNH₄

121. Conductivity (Unit : siemen’s S) is directly proportionally to the area of the vessel and the concentration of the solution in it and is inversely proportional to the length of vessel, then the unit of constant of proportionality is

S m² mol¯¹

S² m² mol

S m mol¯¹

S² m² mol¯²

122. If the standard electrode potential of CU²⁺/Cu electrode is 0.34 V, what is the electrode potential of 0.01 M concentration of Cu²⁺? (T = 298 K)

0.399 V

0.281 V

0.222 V

0.176 V

123. Temperature for standard electrode potential is

273 K

25 C°

310 K

300 K

124. A solution of sodium sulphate was electrolyzed using some inert electrodes. The products at the electrodes are

O₂,H₂

O₂, Na

None of these

O₂, SO₂

125. Partial pressure of a solution component is directly proportional to its mole fraction. This statement is known as

Ostwald’s dilution law

Distribution law

Henry’s law

Raoult’s law

Page 6 of 8

126. The molarity of the solution containing x grams (NH₄)SO₄ in 500 cm³ of the solution is 0.6. What is x

45.1

39.6

40.5

42.7

127. Which substances are mixed to form a buffer solution?

A strong acid and its salt of a strong base

Weak acid and its salt of strong base

Weak acid and its salt of weak base

Strong acid and its salt of weak base

128. The art of electroplating was given by

Thomas Gradam

Edison

Brugan

Faraday

129. If 18 g of glucose (C₆H₁₂C₆) is present in 1000 g of an aqueous solution of glucose it is said to be

1 molal

0.1 molal

1.1 molal

0.5 molal

130. Which of these is not an application of electrolysis?

Electroplating

Manufacture of bleach

Making leather

Rust removal

131. The limiting molar conductivities ʌ’ for NaCl, KBr and KCl are 126, 152 and 150 S cm² respectively. The ʌ’ for NaBr is

176 S cm² mol¯¹

278 S cm² mol¯¹

302 S cm² mol¯¹

128 S cm² mol¯¹

132. Which of the following statement is correct for electrolytic cell?

None of these

Electrons flow from cathode to anode through the external battery

Electrons flow cathode to anode within the electrolytic solution

Migration of ions along with oxidation reaction at anode and reduction reaction at cathode

133. Which has maximum oxidation number

134. What are the ions present in water?

H+ and OH-

H2 and O

H2O

H and OH

135. Best way to prevent rusting iron is by

Putting it in saline water

Both of these

None of these

Making iron cathode

136. Cathodic reaction in the electrolysis of dil. H₂SO₄ is always

Reduction

Oxidation

Both

137. In galvanic cell Zn acts as an anode so its value of standard reduction potential in comparison to coupled electrode would be

Lesser

Greater

None

Sum of reduction and oxidation potentials

138. In electrolysis of NaCl when Pt electrode is taken then H₂ is liberated at cathode while with Hg cathode it forms sodium amalgam

Hg is more inert than Pt

More voltage is required to reduce H⁺ at Hg than at Pt

Conc. Of H⁺ ions is when Pt electrode is taken

Na is dissolved in Hg while it does not dissolve in Pt

139. If the salt bridge is not used between two half cells, then the voltage

Decrease rapidly

Does not change

Drops to zero

Decreases slowly

140. When a metal is dipped in 1 molar of its solution at 298k, then potential set up is called

Standard electrode potential

Electric change

Ionization potential

Electroplating

141. H₂ gas in SHE is filled at a pressure of

750 mm of Hg

800 mm of Hg

760 mm of Hg

780 mm of Hg

142. Time required to deposit one millimole of aluminum metal by the passage of 9.65 amperes through molten electrolyte containing aluminum ion is

30 s

30,000 s

10 s

10,000 s

143. Which of the following statements is FALSE?

All electrochemical reactions involve the transfer of electrons

All voltaic (galvanic) cells involve the use of electricity to initiate nonspontaneous chemical reactions

Reduction occurs at cathode

Oxidation and reduction half-reactions occur at electrodes in electrochemical cells.

144. Alkaline battery has a voltage of

3.5V

4.5V

1.5V

2.5V

145. The vapour pressure of two liquids ‘P’ and ‘Q’ are 80 and 60 torr respectively. The total vapour pressure of solution obtained by mixing 3 mole of P and 2 mol of Q would be

68 torr

140 torr

20 torr

72 torr

146. Corrosion reactions are

Spontaneous acid–base reactions

None of these

Spontaneous redox reactions

Non-spontaneous redox reactions

147. Salt bridge transfers

Anions

Current

Solvent particles

Electrons

148. 18g of glucose is dissolved in 90g of water. The relative lowering of vapour pressure is equal to

1/51

1/5

5.1

149. The EMF of the cell rection Fe²⁺ + zn = Zn²⁺ + feis

+ 1.17 V

– 0.35 V

+ 0.35

– 1.17 V

150. The substance having highest conductivity at room temperature among the following is

0.1 N HCl

Graphite

0.1 N NaCl

Glass

Page 7 of 8

151. Reaction takes place at anode is

Ionization

Hydrolysis

Reduction

Oxidation

152. Azeotropic mixture of HCl and water has

36% HCl

22.2% HCl

20.2% HCl

48% HCl

153. By means of fuel cells, chemical energy may be converted into

Sound energy

Heat energy

Electrical energy

Magnetic energy

154. Colligative properties are the properties of

Concentration solutions behave as nearly non – ideal solutions

Neither a nor b

Both a and b

Dilute solution which behave as nearly ideal solution

155. During a redox reaction, an oxidizing agent

Is oxidized

Gains electrons

Is hydrolysed

Loses electrons

156. How much of NaOH is required to neutralize 1500 cm³ of 0.1 N HCl?

6 g

60 g

40 g

4 g

157. An electrolyte

Possesses ions even in solid state

Gives ions only when dissolved in water

Forms complex ions in solution

Gives ions only when electricity is passed

158. The process of electrical coating of one metal on another to protect, decorate or to have a greater resistance to corrosion is called

Electrolysis

Induction

Electroplating

Conduction

159. When during electrolysis of a solution of AgNO₃, 9650 coulombs of charge pass through the electroplating bath, the mass of silver deposited on the cathode will be

1.08 g

21.6 g

108 g

10.8 g

160. An electric current is passed through silver voltmeter connected to a water voltmeter. The cathode of the silver voltammeter is 0.108 g more at the end of the electrolysis. The volume of oxygen evolved at STP is

11.2 cm³

550 cm³

5.6 cm³

56 cm³

161. When electricity is passed through molten electrolyte consisting of alumina and cryolite, 13.5 g of Al are deposited. The number of faradays of electricity passed must be

1.0

0.5

1.5

2.0

162. The best reducing agent is

F¯

I¯

Cl¯

Br¯

163. A solution contains A, B and C components. The mole fraction A and C are 0.25 and 0.35 respectively. The mole fraction B will be

0.40

0.30

0.25

0.35

164. What will be the density of H₂SO₄ when lead accumulator is recharged?

1.15 cm¯³

1.81 cm¯³

1.25 cm¯³

2.15 cm¯³

165. Density of H₂SO₄ in lead accumulator is

1.25g/cm3

1.20g/cm3

1.3g/cm3

1.15g/cm3

166. Oxidation state of hydrogen in CaH₂ is

-1

-2

167. If 5.85 g of NaCl are dissolved in 90g of water, the mole fraction of NaCl is

0.0196

0.1

0.01

0.2

168. The unit of specific conductivity is

Ohm¯¹ cm¯¹

Ohm¯¹ cm

Ohm cm¯²

Ohm cm¯¹

169. When Cu, Ag, Au and Pt are reacted with acids, these metals do not liberate hydrogen, this is due to the reason that

Very high negative values reduction potential

Very high positive value of reduction potential

Very low ionization potential values

Reduction potentials are negative

170. Electrochemical series is a list of elements arranged into increasing order to either

Ionization potential

Standard oxidation potential

Cell voltage

Standard reduction potential

171. At room temperature, the mole fraction of a solution in 0.25 and the vapour pressure of the solvent is 0.80 atm. Then the lowering of vapour pressure is

0.80

0.60

0.20

0.75

172. What will be the weight of deposited silver on passing 965 coulombs of electricity in solution of AgNO₃?

1.08 g

2.16 g

0.54 g

0.27 g

173. The solubility of a gas in water depends upon

Temperature

Pressure of the gas

Nature of the gas

All of these

174. The number of coulombs required for the deposition of 107.870 g of silver is

10000

96500

48250

193000

175. Potential of Zn is called

Redox

Reduction

Oxidation

It has not potential

Page 8 of 8

176. If a salt bridge is removed between the two half cells, the voltage

Does not change

Increases gradually

Drops to zero

Increases rapidly

177. Corrosion is basically a

Union between two light metals and a heavy metal

Altered reaction in presence of H₂O

Electrochemical phenomenon

Interaction

178. The ionic strength of a solution containing 0.1 mole/kg of KCl and 0.2 mole/kg of CuSO₄ is

0.9

0.2

0.3

0.6

179. The temperature at which the vapour pressure of a liquid becomes equal to external pressure is

Melting point

Boiling point

Inversion point

Sublimation point

180. 50 mL of 10 N H₂SO₄. 25 mL of 12 N HCl and 40 mL of 5N HNO₃ are mixed and the volume of the mixture is made 1000 mL by adding water. The normality of resulting solution will be

9 N

2 N

1 N

3 N

181. Molarity of water is

55.5

182. An oxidizing agent in a chemical reaction in the substance which

Loses electrons

Gains electrons

pH is changed

Acts as a catalyst

183. The strength of solution an element whose electrode potential is to be measured

1 f

1 M

2 M

1 N

184. In alkaline battery the anode is made up of

Cadmium

MnO2

AgO2

185. Pick out the wrong statement. In electrochemical cell

Electrons are released at anode

Salt bridge maintains the electrical neutrality of the solution

Chemical energy is converted into electrical energy

Cathode is regarded as negative electrode

186. For spontaneity of a cell, which is correct?

∆ G = 0, ∆E = 0

∆ G = -ve, ∆ E = 0

∆ G = +ve, ∆ E = 0

∆ G = -ve

187. An aqueous solution freezes at -0.186°C. (Kf = 1.86, Kb = 0.512). What is the elevation in boiling point?

0.512

0.80

0.0512

0.186

188. Electrode potential of Zn is

Oxidation-reduction

Depends on the nature of the coupled electrode

Reduction

Oxidation

189. Calculate the amount of charge flowing in 2 minute in a wire of resistance 10 Ω when a potential difference of 20 V is applied

120 C

20 C

4 C

240 C

190. The cathodic reaction in the electrolysis of dil. H₂SO₄ with Pt electrodes is

Neither oxidation and reduction

Oxidation

Both oxidation and reduction

Reduction

191. Decrease in oxidation number is called

Reduction

All of these

Redox

Oxidation

192. Which of the following is the strongest oxidizing agent?

Pb²⁺

Ag⁺

I₂

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