Free Redox Reactions MCQs with Answers
102 Redox Reactions MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Redox reactions involve oxidation and reduction occurring together, with electrons transferred between species or oxidation numbers changing. The topic covers assigning oxidation states, identifying oxidizing and reducing agents, balancing redox equations by oxidation number or half-reaction methods, and connecting chemical changes with galvanic and electrolytic cells.
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102 questions · page 4 of 6
- A. Mercury
- B. Titanium
- C. Graphite
- D. Copper
Explanation: The explanation for this question will be added soon.
Correct answer: Titanium- A. Hall's
- B. Nelson's
- C. Down's
- D. Hoope's
Explanation: The explanation for this question will be added soon.
Correct answer: Hoope's- A. NaCl, NaClO, H2O
- B. NaCl , NaClO3 , H2O
- C. NaClO , NaClO3, H2O
- D. NaCl , H2O
Explanation: Cold dilute sodium hydroxide and chlorine gas reaction is disproportionation.
Correct answer: NaCl, NaClO, H2O- A. Electroplating
- B. Conductivity
- C. Galvanizing
- D. Metallurgy
Explanation: In electroplating, we have the object replacing the cathode and the metal, the anode.
Correct answer: Electroplating- A. Lead-acid accumulator
- B. H2 - O2 fuel cell
- C. Silver oxide battery
- D. Alkaline battery
Explanation: All the sources listed except H2 - O2 fuel cells produce electrical energy but they need to be disposed of eventually.
Correct answer: H2 - O2 fuel cell- A. Water
- B. HCI
- C. Na+
- D. NaCl
Explanation: In a diaphragm cell, which is a type of electrolytic cell used for the production of chlorine and sodium hydroxide, hydrogen gas is…
Correct answer: Water- A. (NH4)2Cr2O7
- B. K2Cr207
- C. Zn(CIO3)2
- D. KCIO3
Explanation: Equations for each reaction: A- (NH4)2Cr2O7 (aq) ⇌ N2 (g) + 4 H2O (l) + Cr2O3 (s) [No oxygen released] B- 4 K2Cr2O7(1) ⇌ 4K2CrO4(1) + 2…
Correct answer: (NH4)2Cr2O7- A. Graphite
- B. Copper
- C. Iron
- D. Silver
Explanation: The graphite anode has no reaction with chlorine, which is liberated at the anode.
Correct answer: Graphite- A. Free charge
- B. Electron
- C. Protons
- D. Zinc ions
Explanation: Option BCu+2 ions from the solution pick up the ELECTRONS at Cu electrode and get reduced to copper atoms ,hence Cu acts as a cathode and…
Correct answer: Electron- A. Graphite
- B. Copper
- C. Iron
- D. Silver
Explanation: In a Down's cell, which is an electrolytic cell used for the production of sodium metal through the electrolysis of molten sodium chloride…
Correct answer: Graphite- A. Free electrons
- B. Positive ions
- C. Negative ions
- D. Both Options B and C are correct
Explanation: In electrolysis, current is carried through the electrolytic solution inside the cell by positive and negative ions using…
Correct answer: Both Options B and C are correct- A. Electrons
- B. Charges
- C. Energy
- D. Hydrogen ions
Explanation: Redox reactions (oxidation-reduction reactions) are actually the transfer of electrons.
Correct answer: Electrons- A. Sodium
- B. Hydrogen
- C. Chlorine
- D. Oxygen
Explanation: Chloride ions (Cl⁻) are attracted to the positive electrode (anode) during the electrolysis of a dilute solution of NaCl.
Correct answer: Chlorine- A. Copper sulphate
- B. Copper chloride
- C. Zinc Chloride
- D. Zinc Sulphate
Explanation: Zinc, in a voltaic cell, is always dipped in zinc sulfate to get an excess of Zn2+ ions.
Correct answer: Zinc Sulphate- A. (NH4)2Cr2O7
- B. K2Cr2O7
- C. Zn(ClO3)2
- D. KClO3
Explanation: This compound, also known as ammonium dichromate, decomposes upon heating to form chromium (lll) oxide, nitrogen gas, and water vapor.
Correct answer: (NH4)2Cr2O7- A. Copper metal
- B. Copper ions
- C. Hydrogen
- D. Oxygen
Explanation: Since reduction takes place cupric ions present in the electrolyte gain two electrons and get converted into copper metal.
Correct answer: Copper metal- A. Cd
- B. Ni(OH)2
- C. Ni
- D. NiO2
Explanation: Explanation:The correct option is NiO2 because the cathode in a nickel-cadmium battery is typically composed of nickel oxyhydroxide…
Correct answer: NiO2- A. Tin plating
- B. Zinc plating
- C. Nickel plating
- D. Copper plating
Explanation: Explanation:The most durable metal plating on iron to protect against corrosion is zinc plating.
Correct answer: Zinc plating- A. Hydrolysis reaction
- B. Oxidation reaction
- C. Redox reaction
- D. Reduction reaction
Explanation: The correct answer is C: Redox reaction. In a voltaic cell, the production of electricity is due to redox reactions, where oxidation and…
Correct answer: Redox reaction- A. Zn+2 + Cu → Cu+2 + Zn
- B. Zn + MgSO4 → ZnSO4 + Mg
- C. Fe + CuSO4 → FeSO4 + Cu
- D. Cd + MgSO4 → CdSO4 + Mg
Explanation: Fe + CuSO₄ → FeSO₄ + Cu is feasible because iron has a lower reduction potential (-0.44 V) than copper (+0.34 V), meaning iron is more…
Correct answer: Fe + CuSO4 → FeSO4 + Cu