This quiz works best with JavaScript enabled. Home > Class 11 > Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions – Quiz 19 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 19 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. WRITE THIS OUT ON PAPER, YOU MAY USE THE ANSWER TO THIS PROBLEM AGAIN IN ANOTHER QUESTION:Balance the following ACIDIC reactions using changing oxidation number method.MnO$_{4}$$^{-}$(aq) + H$^{+}$(aq) + I$^{-}$ (aq) $\rightarrow$ Mn$^{2+}$(aq) + I$_{2}$(s)Water is a product of this reaction. What is the coefficient of water in the final balanced equation? A) 8. B) 5. C) 2. D) 16. Show Answer Correct Answer: A) 8. 2. An element's oxidation numbers changed from zero to +2 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: A) It was oxidized. 3. In a redox reaction, what happens to the oxidation number of the element that is reduced? A) It increases. B) It decreases. C) It remains the same. D) It becomes zero. Show Answer Correct Answer: B) It decreases. 4. How does increasing the efficiency of a fuel cell impact its operation? A) Increases the amount of fuel required. B) Decreases the electrical output. C) Reduces the environmental benefits. D) Enhances the conversion of chemical energy to electrical energy. Show Answer Correct Answer: D) Enhances the conversion of chemical energy to electrical energy. 5. Which one below is redox reaction? A) $CaCO_3+2HCl\longrightarrow CaCl_2+CO_2+H_2O$. B) $CaO+H_2O\longrightarrow Ca\left(OH\right)_2$. C) $SO_2+2H_2S\longrightarrow3S+2H_2O$. D) $NaCl+AgNO_3\longrightarrow AgCl+NaNO_3$. Show Answer Correct Answer: C) $SO_2+2H_2S\longrightarrow3S+2H_2O$. 6. The oxidation number on the central carbon atom in O=C=C=C=O and the average oxidation number of carbon, respectively are A) 0, +1.33. B) +4, -1.33. C) +2, 0. D) 0, +2. Show Answer Correct Answer: A) 0, +1.33. 7. Describe the steps to balance a redox reaction in an acidic medium. A) Balance redox reactions in acidic medium by using half-reactions, balancing atoms and charges, and combining them. B) Combine all reactants without balancing. C) Ignore the charge balance completely. D) Use only oxidation numbers to balance. Show Answer Correct Answer: A) Balance redox reactions in acidic medium by using half-reactions, balancing atoms and charges, and combining them. 8. What is the oxidation number of Cl in Cl$_{2}$? A) -1. B) +1. C) Cannot be determined. D) 0. Show Answer Correct Answer: D) 0. 9. Which expression represents the oxidation of the copper(I) ion? A) Cu$^{+}$$\rightarrow$ Cu$^{2+}$ + e$^{-}$. B) Cu $\rightarrow$ Cu$^{+}$ + e$^{-}$. C) Cu$^{+}$ + e$^{-}$$\rightarrow$ Cu$^{0}$. D) Cu$^{+}$ + e$^{-}$ $\rightarrow$ Cu$^{2+}$. Show Answer Correct Answer: A) Cu$^{+}$$\rightarrow$ Cu$^{2+}$ + e$^{-}$. 10. What is the primary function of the electrolyte in a fuel cell? A) To cool down the cell components. B) To act as a fuel source. C) To facilitate the flow of ions between the anode and cathode. D) To store electrical energy. Show Answer Correct Answer: C) To facilitate the flow of ions between the anode and cathode. 11. Solutions of acidified potassium manganate (VII) (oxidising agent) and potassium iodide (reducing agent) are mixed together. The colour of the resulting mixture is brown. This is because A) The products are colourless and brown. B) The products are puple and brown. C) The products are the same colour as the reactants. D) Potassium displaced iodine from potassium iodide. Show Answer Correct Answer: A) The products are colourless and brown. 12. In the electrolysis of an aqueous solution, which ONE of the following statements is NOT true? A) Electrons are lost by one of the species at the anode. B) Oxidation takes place at the positive electrode. C) Reduction takes place at the cathode. D) Electrons flow around the circuit from the cathode to the negative end of the battery. Show Answer Correct Answer: D) Electrons flow around the circuit from the cathode to the negative end of the battery. 13. What is the oxidation number of X in XO$_{4}$$^{-}$? A) +4. B) +5. C) +7. D) +8. Show Answer Correct Answer: C) +7. 14. Explain the difference between a cation and an anion in terms of charge. A) Cations have a positive charge, while anions have a negative charge. B) Cations have a negative charge, while anions have a positive charge. C) Both cations and anions have no charge. D) Cations are neutral, and anions are positively charged. Show Answer Correct Answer: A) Cations have a positive charge, while anions have a negative charge. 15. What is the oxidation number of O in CO$_{2}$? A) +2. B) -1. C) +4. D) -2. Show Answer Correct Answer: D) -2. 16. Which of the following is an oxidising agent? A) Chlorine. B) Sulphur dioxide. C) Hydrogen sulphide. D) Potassium bromide. Show Answer Correct Answer: A) Chlorine. 17. What is the oxidation state of manganese in K2MnO4? A) +2. B) +6. C) +4. D) +3. Show Answer Correct Answer: B) +6. 18. What is the product of the Haber process? A) Carbon dioxide. B) Ammonia. C) Hydrogen peroxide. D) Sulfuric acid. Show Answer Correct Answer: B) Ammonia. 19. What is the purpose of the salt bridge in a galvanic cell? A) To increase the voltage of the cell. B) To allow the flow of electrons between the two half-cells. C) To prevent the mixing of the solutions in the two half-cells. D) To maintain electrical neutrality by allowing the flow of ions. Show Answer Correct Answer: D) To maintain electrical neutrality by allowing the flow of ions. 20. During which process does an atom gain one or more electrons? A) Transmutation. B) Reduction. C) Oxidation. D) Neutralization. Show Answer Correct Answer: B) Reduction. 21. What is the primary process that occurs in a redox reaction? A) Heat transfer. B) Electron transfer. C) Proton transfer. D) Neutron transfer. Show Answer Correct Answer: B) Electron transfer. 22. An element undergoes oxidation when A) It loses oxygen. B) It gains electrons. C) It loses hydrogen. D) Its oxidation number decreases. Show Answer Correct Answer: C) It loses hydrogen. 23. Another name for a "oxidation-reduction" reaction is A) Chemical reaction. B) Neutralization reaction. C) Redox reaction. D) Nuclear reaction. Show Answer Correct Answer: C) Redox reaction. 24. What is the main component of a galvanic cell? A) Two different metals. B) A gas. C) A non-metal. D) A single metal. Show Answer Correct Answer: A) Two different metals. 25. The ionic equation shows the reaction between zinc (Zn) and hydrochloric acid.Zn + 2H$^{+}$ $\rightarrow$ Zn$^{2+}$ + H$_{2}$What change takes place in the zinc? A) It gains electrons. B) Its oxidation state increases. C) It is reduced. D) It gains hydrogen. Show Answer Correct Answer: B) Its oxidation state increases. ← PreviousNext →Related 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 3Class 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 9Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 10 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books