Free Electrochemistry MCQs with Answers
696 Electrochemistry MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Electrochemistry describes electron transfer through oxidation and reduction, identifies oxidizing and reducing agents, and applies oxidation numbers to balance redox equations. It also covers electrode potential and the standard hydrogen electrode, which provides the reference for comparing the reduction tendencies of other electrodes.
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Read the Electrochemistry notesFree MDCAT chapter notes with key terms696 questions · page 30 of 35
- A. N
- B. F
- C. O
- D. CI
Explanation: Fluorine is very strong oxidizing agent and is at the bottom of ECS. Indicating its highest Eered= +2.87V.
Correct answer: F- A. H2
- B. CI2
- C. O2
- D. Na
Explanation: During electrolysis of brine, chlorine is obtained on anode.
Correct answer: CI2- A. It is apparent charge on an atom in a compound
- B. Its value is either zero, positive or negative
- C. It can be variable
- D. Xenon (Xe) can show maximum oxidation state +6 in its compounds
Explanation: Oxidation state or oxidation number, is the hypothetical charge of an atom if all of its bonds to other atoms were fully ionic.
Correct answer: Xenon (Xe) can show maximum oxidation state +6 in its compounds- A. They may be get deposited/released on the electrode surface
- B. They may go out in the form of gases
- C. Electrolytic material may get dissolved into the solution as ions
- D. In Nelson cell, Na metal is a primary product
Explanation: The correct answer is D) In Nelson cell, Na metal is a primary product.
Correct answer: In Nelson cell, Na metal is a primary product- A. NaCl(aq)
- B. NaCI(molten)
- C. NaCl(s)
- D. Silver metal
Explanation: The correct answer is C) NaCl(s). Solid sodium chloride (table salt) is not a conductor of electricity because its ions are not free to…
Correct answer: NaCl(s)- A. It involves conversion of electrical energy into chemical energy
- B. Anode has negative charge and cathode has positive charge in this cell
- C. It is reverse of addition reaction
- D. It is endothermic process
Explanation: The correct answer is B) Anode has a negative charge, and cathode has a positive charge in this cell.
Correct answer: Anode has negative charge and cathode has positive charge in this cell- A. A
- B. B
- C. C
- D. D
Explanation: The correct answer is A) Option A presents the correct decreasing order of discharge of positive ions at the cathode based on the…
Correct answer: A- A. Na reacts with water
- B. Na+ is more stable than Na atom
- C. Na+ reacts with CI ion in the solution
- D. Reduction of H2O is preferred to Na+
Explanation: This option is the correct reason why Na metal cannot be produced by electrolysis of an aqueous solution of NaCl.
Correct answer: Reduction of H2O is preferred to Na+- A. A
- B. B
- C. C
- D. D
Explanation: To act as an oxidizing agent the hydrogen itself has to be reduced. The oxidation number of hydrogen in H2 is 0 and in NaH is -1, it is…
Correct answer: C- A. 9
- B. 6
- C. 3
- D. 2
Explanation: In an acidic medium Cr is reduced from +6 to +3 as: Cr2O7-2+ 14H+ +6e- → 2Cr+3 + 7H2O and Fe2+ is oxidized to Fe3+ as: Fe2+→ Fe3++ e- So…
Correct answer: 6- A. The smaller the E°red, the greater the reducing power of a metal
- B. E°rcd of Li1 is minimum (-3.04V)
- C. The greater the E°red, the greater the oxidizing power of a non-metal
- D. E°red of Cl2 is maximum (+2.87V)
Explanation: The statement that E°red of Cl2 is maximum (+2.87V) is incorrect. Chlorine has a high E°red because it is a strong oxidizing agent.
Correct answer: E°red of Cl2 is maximum (+2.87V)- A. It is used as a reference electrode
- B. its E°red is zero or less than zero
- C. When it is connected to zinc electrode in a galvanic cell, it act as cathode
- D. When it is connected to Cu electrode in a galvanic cell, it act as anode
Explanation: The standard reduction potential (E°red) of the standard hydrogen electrode is defined to be exactly 0 volts. It cannot be less than zero.
Correct answer: its E°red is zero or less than zero- A. Na is deposited
- B. O2 gas is released
- C. Neither Na or H2 is released
- D. H2 gas is released
Explanation: On the electrolysis of aqueous solution of Na2SO4 by using inert electrodes, hydrogen gas is released at the cathode electrode.The reason…
Correct answer: H2 gas is released- A. H2gas is released
- B. O2 gas is released
- C. SO2 gas is released
- D. Neither O2 or SO2 gas is released
Explanation: On the electrolysis of dilute H2SO4 solution by using inert electrodes, oxygen gas is released at the anode electrode.The reason for this…
Correct answer: O2 gas is released- A. Net charge should be same on each side
- B. Total number of atoms should be same
- C. Total number of ions should be same
- D. Both A and B
Explanation: Ion-Electron Method (Half-Reaction Method): The ion-electron method, also known as the half-reaction method, is a technique used to…
Correct answer: Both A and B- A. Graphite
- B. Copper
- C. Iron
- D. Inert materia
Explanation: In Down's cell, which is used for the electrolytic production of sodium metal, the cathode is made up of iron.In the Down's cell, the…
Correct answer: Iron- A. Aqueous NaCI
- B. Aqueous NaNO3
- C. Fused NaCI
- D. Fused NaNO3
Explanation: Down's cell is used for the electrolysis of molten sodium chloride (NaCl) to produce sodium metal and chlorine gas.
Correct answer: Fused NaCI- A. An Acid
- B. A base
- C. Its own ions
- D. Water
Explanation: When a metal is dipped into a solution containing its own ions (in the form of a salt), electrode potential can be developed.
Correct answer: Its own ions- A. Buffer
- B. Spectator substance
- C. Reaction intermediate
- D. None of these
Explanation: An intermediate is a species which appears in the mechanism of a reaction, but not in the overall balanced equation.
Correct answer: Reaction intermediate- A. E
- B. E-1
- C. E°
- D. ∂
Explanation: In electrochemistry the electrode potential is the electromotive force of a cell built of two electrodes. It is denoted by the sign E.
Correct answer: E°