This quiz works best with JavaScript enabled. Home > Cbse > Class 11 > Science > Chemistry Part Ii > Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions – Quiz 3 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 3 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. What is the oxidation number of hydrogen in MgH$_{2}$? A) +2. B) -2. C) +1. D) -1. Show Answer Correct Answer: D) -1. 2. Which component is not part of a basic fuel cell? A) Salt bridge. B) Electrolyte. C) Anode. D) Cathode. Show Answer Correct Answer: A) Salt bridge. 3. Which of the following represents oxidation? A) C $\rightarrow$ CH$_{4}$. B) Zn $\rightarrow$ ZnO. C) Fe$^{3+}$ $\rightarrow$ Fe$^{2+}$. D) Cl$_{2}$ $\rightarrow$ 2Cl$^{-}$. Show Answer Correct Answer: B) Zn $\rightarrow$ ZnO. 4. Identify the oxidizing agent in a redox reaction. A) The substance that acts as a catalyst in the reaction. B) The substance that gains electrons and is reduced. C) The substance that remains unchanged during the reaction. D) The substance that loses electrons and is oxidized. Show Answer Correct Answer: B) The substance that gains electrons and is reduced. 5. Which substance is reduced in the following reaction? NaOH + Li $\rightarrow$ LiOH + Na A) O. B) H. C) Na. D) Li. Show Answer Correct Answer: C) Na. 6. In the reaction @@ext{2H} ..... 2ext{O} ..... 2 ightarrow ext{2H} ..... 2ext{O} + ext{O} ..... 2@@, what is the oxidizing agent? A) $\text{H}_2\text{O}_2$. B) $\text{H}_2\text{O}$. C) $\text{O}_2$. D) None of the above. Show Answer Correct Answer: A) $\text{H}_2\text{O}_2$. 7. Given the reaction for the corrosion of aluminum:4 Al + 3 O$_{2}$ $\rightarrow$ 2 Al$_{2}$O$_{3}$Which half-reaction correctly represents the oxidation that occurs? A) O$_{2}$ + 4e$^{-}$ $\rightarrow$ 2 O$^{2-}$. B) Al $\rightarrow$ Al$^{3+}$ + 3e$^{-}$. C) Al + 3e-$^{ }$ $\rightarrow$ Al$^{3+}$. D) O$_{2}$ $\rightarrow$ 2 O$_{2}$-+ 4e$^{-}$. Show Answer Correct Answer: B) Al $\rightarrow$ Al$^{3+}$ + 3e$^{-}$. 8. In the following reaction, which term applies to chlorine?Ca + Cl$_{2}$ $\rightarrow$ CaCl$_{2}$ A) Oxidising agent. B) Reducing agent. C) Spectator ion. D) Accelerator ion. Show Answer Correct Answer: A) Oxidising agent. 9. What is the role of an oxidizing agent? A) It gains electrons. B) It is oxidized in the reaction. C) It loses electrons. D) It is reduced in the reaction. Show Answer Correct Answer: D) It is reduced in the reaction. 10. What is the oxidation state of sulfur in the sulfate ion (SO42-)? A) +4. B) +10. C) +6. D) +8. Show Answer Correct Answer: C) +6. 11. Which change indicates reduction? A) Fe becomes Fe$^{2+}$. B) Fe$^{2+}$ becomes Fe. C) Ag becomes Ag$^{+}$. D) None of the above. Show Answer Correct Answer: B) Fe$^{2+}$ becomes Fe. 12. What is the name of the positive electrode? A) Cathode. B) Anode. C) All the above. D) None of the above. Show Answer Correct Answer: B) Anode. 13. What will be the result of the following:Br$_{2 }$+ NaF $\rightarrow$ A) Bromine will replace Na. B) Br will replace F. C) Na will replace Br. D) No reaction will occur. Show Answer Correct Answer: D) No reaction will occur. 14. What is the oxidation state of a lone element? A) It is always 1. B) It is the same as in a compound. C) It is its most likely oxidation state. D) It is always 0. Show Answer Correct Answer: D) It is always 0. 15. The correct description about redox reaction is A) Oxygen is definitely present. B) The oxidising agent itself carries out oxidation. C) Electron transfer definitely takes place. D) Oxidation takes place before reduction. Show Answer Correct Answer: C) Electron transfer definitely takes place. 16. How do you identify the reducing agent in a redox reaction? A) The reducing agent is always a metal. B) The reducing agent is the substance that is reduced. C) The reducing agent is the substance that is oxidized. D) The reducing agent gains electrons during the reaction. Show Answer Correct Answer: C) The reducing agent is the substance that is oxidized. 17. The basis of redox reactions is the A) Loss, gain, or bias of electrons. B) Recombination of atoms in molecules. C) Gain or loss of oxygen atom. D) Change in oxidation numbers. Show Answer Correct Answer: D) Change in oxidation numbers. 18. What is the IUPAC name and oxidation number of copper element in the compound Cu$_{2}$O? A) Copper(I) oxide; +1. B) Copper(I) oxide; +2. C) Copper(II) oxide; +1. D) Copper(II) oxide; +2. Show Answer Correct Answer: A) Copper(I) oxide; +1. 19. Which process involves the transfer of electrons? A) Double replacement. B) Neutralization. C) Oxidation-reduction. D) Sublimation. Show Answer Correct Answer: C) Oxidation-reduction. 20. Which element undergoes reduction here:N$_{2}$ + 3H$_{2}$ $\rightarrow$ 2NH$_{3}$ A) N$_{2}$. B) H$_{2 }$. C) NH$_{3}$. D) None. Show Answer Correct Answer: A) N$_{2}$. 21. What metal in reactivity series is extracted by electrolysis? A) Lead. B) Lithium. C) Iron. D) Gold. Show Answer Correct Answer: B) Lithium. 22. The process defined as the loss of electrons. A) Oxidizing agnet. B) Reduction. C) Redox. D) Oxidation. Show Answer Correct Answer: D) Oxidation. 23. Cl$_{2}$ + 2e-$\rightarrow$ 2Cl $^{-}$ is an example of: A) A chemical reaction. B) Redox. C) Reduction. D) Oxidation. Show Answer Correct Answer: C) Reduction. 24. An element's oxidation numbers became more negative during a reaction. What happened to that element? A) It was oxidized. B) It was reduced. C) It was both oxidized and reduced. D) It was neither oxidized nor reduced. Show Answer Correct Answer: B) It was reduced. 25. In the reaction $\text{Zn} + \text{CuSO}_4 \rightarrow \text{ZnSO}_4 + \text{Cu}$ A) Oxygen (O). B) Zinc (Zn). C) Copper (Cu). D) Sulphur (S). Show Answer Correct Answer: B) Zinc (Zn). 26. Is calcium oxidized or reduced in the following reaction? 2 CaO$\rightarrow$ 2 Ca + O$_{2}$ A) Oxidized. B) Reduced. C) All the above. D) None of the above. Show Answer Correct Answer: B) Reduced. 27. Which one of the following is the best oxidizing agent? A) Li. B) Ca. C) O$_{2}$. D) H$_{2}$. E) Na. Show Answer Correct Answer: C) O$_{2}$. 28. Describe the steps involved in balancing a redox reaction using the half-reaction method. A) Identifying only the oxidizing agent. B) The steps involved in balancing a redox reaction using the half-reaction method include identifying half-reactions, balancing atoms and charges, and combining them. C) Combining half-reactions without balancing. D) Ignoring charge balance during the process. Show Answer Correct Answer: B) The steps involved in balancing a redox reaction using the half-reaction method include identifying half-reactions, balancing atoms and charges, and combining them. 29. Which half-reaction shows conservation of charge? A) Cu$^{2+}$ + 2e$^{-}$ $\rightarrow$ Cu. B) Cu$^{2+}$ $\rightarrow$ Cu + 2e$^{-}$. C) Cu$^{+}$ $\rightarrow$ Cu + e$^{-}$. D) Cu + e$^{-}$ $\rightarrow$ Cu$^{+}$. Show Answer Correct Answer: A) Cu$^{2+}$ + 2e$^{-}$ $\rightarrow$ Cu. 30. In the reaction @@ext{Fe} + ext{CuSO} ..... 4 ightarrow ext{FeSO} ..... 4 + ext{Cu}@@, which element is reduced? A) Oxygen (O). B) Copper (Cu). C) Iron (Fe). D) Sulfur (S). Show Answer Correct Answer: B) Copper (Cu). 31. Aluminium reacts with iron (III) oxide as shown. iron(III) oxide + aluminium $\rightarrow$ iron + aluminium oxide Which statement about this reaction is correct? A) Aluminium oxide is reduced. B) Iron (III) oxide is reduced. C) Iron is oxidised. D) Aluminium is oxidised. Show Answer Correct Answer: D) Aluminium is oxidised. 32. In a redox reaction, what is the substance that gets reduced called? A) Electrolyte. B) Oxidizing agent. C) Reducing agent. D) Catalyst. Show Answer Correct Answer: C) Reducing agent. 33. The standard cell potential for the voltaic cell based on the reaction below is ..... V. 2 Cr (s) + 3 Fe$^{2+ }$(aq) $\rightarrow$ 3 Fe (s) + 2 Cr$^{3+ }$(aq) A) +0.30. B) +3.10. C) -0.16. D) +0.83. E) +2.80. Show Answer Correct Answer: A) +0.30. 34. What is an example of an industrial application of redox chemistry? A) The Haber process. B) Distillation. C) Filtration. D) Crystallization. Show Answer Correct Answer: A) The Haber process. 35. What is the oxidation number of oxygen in water? A) -2. B) -1. C) +2. D) 0. E) +1. Show Answer Correct Answer: A) -2. 36. What is the purpose of electrolysis? A) To break down compounds. B) To combine elements. C) To increase temperature. D) To create new compounds. Show Answer Correct Answer: A) To break down compounds. 37. How can you balance a redox reaction using the half-reaction method? A) Use the half-reaction method to balance redox reactions. B) Use the oxidation state method to balance redox reactions. C) Combine all reactants and products without separating them. D) Ignore the charges and balance only the number of atoms. Show Answer Correct Answer: A) Use the half-reaction method to balance redox reactions. 38. Assertion:Fe reacts with HCl to produce H$_{2}$.Reason:Fe is better reducing agent than H$_{2}$. A) Both assertion and reason are true and the reason is the correct explanation of asserton. B) Both assertion and reason are true but the reason is not the correct explanation of asserton. C) Both assertion and reason are false. D) Assertion is true and reason is false. Show Answer Correct Answer: A) Both assertion and reason are true and the reason is the correct explanation of asserton. 39. This electrode loses mass A) Anode. B) Cathode. C) All the above. D) None of the above. Show Answer Correct Answer: A) Anode. 40. Define oxidation in terms of electron transfer. A) Oxidation is the process of breaking down molecules. B) Oxidation is the process of combining with oxygen. C) Oxidation is the process in which an atom, ion, or molecule loses electrons. D) Oxidation is the process in which an atom, ion, or molecule gains electrons. Show Answer Correct Answer: C) Oxidation is the process in which an atom, ion, or molecule loses electrons. 41. In which of the following compounds, oxygen has the highest oxidation state and in which one, the lowest oxidation state-OF$_{2}$, H$_{2}$O$_{2}$, KO$_{2}$, O$_{2}$F$_{2}$ A) Highest-OF$_{2}$, Lowest-KO$_{2}$. B) Highest-KO$_{2}$, Lowest-H$_{2}$O$_{2}$. C) Highest-KO$_{2}$, Lowest-H$_{2}$O$_{2}$. D) Highest-OF$_{2}$, Lowest-H$_{2}$O$_{2}$. Show Answer Correct Answer: A) Highest-OF$_{2}$, Lowest-KO$_{2}$. 42. Half-reactions can be written to represent all A) Double-replacement reactions. B) Neutralization reactions. C) Fission and fusion reactions. D) Oxidation and reduction reactions. Show Answer Correct Answer: D) Oxidation and reduction reactions. 43. Which mnemonic device is commonly used to remember oxidation and reduction? A) PEMDAS. B) HOMES. C) OIL RIG. D) ROY G BIV. Show Answer Correct Answer: C) OIL RIG. 44. What is the oxidation number of Sulfide ion, S$^{2-}$? A) -1. B) 0. C) +2. D) -2. Show Answer Correct Answer: D) -2. 45. Which one of the followings would result in a displacement reaction? A) Iron with magnesium chloride. B) Gold with silver nitrate. C) Magnesium with iron chloride. D) Iron with Zinc Sulphate. Show Answer Correct Answer: C) Magnesium with iron chloride. 46. Which species undergoes a loss of electrons?Fe$_{(s)}$ + Cl$_{2(g)}$$\rightarrow$Fe$^{2+}$$_{(aq)}$$^{ }$+ Cl$^{-}$$_{(aq)}$ A) Cl$_{2}$. B) Fe$^{2+}$. C) Cl$^{-}$. D) Fe. Show Answer Correct Answer: D) Fe. 47. What is the role of oxidation numbers in redox reactions? A) To balance chemical equations. B) None of the above. C) To keep track of electron movement. D) To determine the color of compounds. Show Answer Correct Answer: C) To keep track of electron movement. 48. What are cations and anions in the context of redox reactions? A) Cations are positively charged ions; anions are negatively charged ions. B) Cations are negatively charged ions; anions are positively charged ions. C) Cations are neutral particles; anions are charged particles. D) Cations are found in the nucleus; anions are found in the electron cloud. Show Answer Correct Answer: A) Cations are positively charged ions; anions are negatively charged ions. 49. What does a redox reaction involve? A) Both oxidation and reduction. B) Only reduction. C) Neither oxidation nor reduction. D) Only oxidation. Show Answer Correct Answer: A) Both oxidation and reduction. 50. What is the oxidation number of Fe in FeO? A) -1. B) +1. C) +2. D) -2. Show Answer Correct Answer: C) +2. 51. Which of the following statements refers to an oxidation process? A) Oxygen is removed from carbon dioxide. B) Chlorine accepts electrons. C) Hydrogen is added to ethene. D) Increase in the oxidation number of magnesium metal. Show Answer Correct Answer: D) Increase in the oxidation number of magnesium metal. 52. What is the role of an oxidising agent in a redox reaction? A) It donates protons. B) It accepts protons. C) It donates electrons. D) It accepts electrons. Show Answer Correct Answer: D) It accepts electrons. 53. In which of the following compounds, an element exhibits two different oxidation states? A) N$_{3}$H. B) N$_{2}$H$_{4}$. C) NH$_{2}$OH. D) NH$_{4}$NO$_{3}$. Show Answer Correct Answer: D) NH$_{4}$NO$_{3}$. 54. As the pH of a solution gets lower, the solution becomes more ..... A) Basic (or alkaline). B) Ionic. C) Acidic. D) Neutral. Show Answer Correct Answer: C) Acidic. 55. What is the outcome when calcium reacts with iron sulfate? A) No reaction occurs. B) Calcium and iron form a compound. C) Calcium displaces iron. D) Iron displaces calcium. Show Answer Correct Answer: C) Calcium displaces iron. 56. The atomic number of Element Z is 13. The oxidation state of an ion of Element Z would MOST probably be A) -3. B) +5. C) -5. D) +3. Show Answer Correct Answer: D) +3. 57. In the reaction CuO + H$_{2}$ $\rightarrow$ Cu + H$_{2}$O, which element is reduced? A) Copper. B) Oxygen. C) Hydrogen. D) None. Show Answer Correct Answer: A) Copper. 58. Which of the following is a condition for a standard cell? A) 0.1 M concentration for solutions. B) 100 kPa pressure for a gas. C) 273 K temperature. D) Measured against zinc. Show Answer Correct Answer: B) 100 kPa pressure for a gas. 59. Which of the following species is the strongest oxidizing agent under standard-state conditions? A) Cl$_{2}$(g). B) Ag$^{+}$(aq). C) Al$^{3+}$(aq). D) H$^{+}$(aq). E) H$_{2}$(g). Show Answer Correct Answer: A) Cl$_{2}$(g). 60. What happens to the oxidation number of an element that is oxidized? A) The oxidation number increases. B) The oxidation number remains the same. C) The oxidation number fluctuates. D) The oxidation number decreases. Show Answer Correct Answer: A) The oxidation number increases. ← PreviousNext →Related QuizzesScience QuizzesClass 11 QuizzesClass 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 1Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 2Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 4Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 5Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 6Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 7Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 8Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 9 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books