This quiz works best with JavaScript enabled. Home > Class 11 > Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions – Quiz 20 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 20 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Which of the following statements is true about redox reactions? A) Oxidation and reduction occur simultaneously. B) Oxidation involves gain of electrons. C) Oxidation and reduction occur independently. D) Reduction involves loss of electrons. Show Answer Correct Answer: A) Oxidation and reduction occur simultaneously. 2. What is the oxidation number assigned to manganese in KMnO$_{4}$? A) $^{+}$7. B) $^{+}$2. C) $^{+}$4. D) $^{+}$3. Show Answer Correct Answer: A) $^{+}$7. 3. What is the oxidation state of Pb in PbO? A) +2. B) +4. C) 0. D) -2. Show Answer Correct Answer: A) +2. 4. Which pair could be spectator ions? A) NH$_{4}$$^{+}$ and Cl$^{-}$. B) Ca$^{+2}$ and OH$^{-}$. C) Ag+ and Br-. D) Sr$^{+2}$ and CO$_{3}$$^{-2}$. Show Answer Correct Answer: A) NH$_{4}$$^{+}$ and Cl$^{-}$. 5. In the following reaction:2CuO (s) + C (s) $\rightarrow$ 2Cu (s) + CO$_{2}$ (g)What undergoes reduction? A) Copper (Cu). B) Carbon (C). C) Copper ions (Cu$^{2+}$). D) Carbon dioxide (CO$_{2}$). Show Answer Correct Answer: C) Copper ions (Cu$^{2+}$). 6. The electrode potential for a redox reaction is: A) The difference between the electrode potential for the oxidation reaction and the reduction reaction. B) The product between the electrode potential for the oxidation reaction and the reduction reaction. C) The quotient between the electrode potential for the oxidation reaction and the reduction reaction. D) The sum between the electrode potential for the oxidation reaction and the reduction reaction. Show Answer Correct Answer: D) The sum between the electrode potential for the oxidation reaction and the reduction reaction. 7. Identify the reducing agent in the following reaction:$2Al + 3Cu^{2+} \rightarrow 2Al^{3+} + 3Cu$ A) $Al$. B) $Cu^{2+}$. C) $Al^{3+}$. D) $Cu$. Show Answer Correct Answer: A) $Al$. 8. What is the oxidation state of chromium in K$_{2}$Cr$_{2}$O$_{7}$? A) -6. B) -7. C) +6. D) +7. Show Answer Correct Answer: C) +6. 9. Why is electron flow compared to economic transactions? A) Because electrons are traded in markets. B) Because electron flow drives chemical change like money drives economic transactions. C) Because electrons are expensive. D) Because electrons are used as currency. Show Answer Correct Answer: B) Because electron flow drives chemical change like money drives economic transactions. 10. Which species functions as the oxidizing agent in the following oxidation-reduction reaction?Zn$_{(s)}$ + Pt$^{2+}$$_{(aq) }$$\rightarrow$ Pt$_{(s)}$ + Zn$^{2+}$$_{(aq)}$ A) Pt$_{(s)}$. B) Zn$^{2+}$$_{(aq)}$. C) Pt$^{2+}$$_{(aq)}$. D) Zn$_{(s)}$. E) None of these, as this is not a redox reaction. Show Answer Correct Answer: C) Pt$^{2+}$$_{(aq)}$. 11. What does the term 'redox' stand for? A) Reactive and oxygen. B) Red energy and oxidation. C) Reduction or oxygen. D) Reduction and oxidation. Show Answer Correct Answer: D) Reduction and oxidation. 12. What is the oxidation state of sulfur in HSO$_{4}$$^{-}$ A) +4. B) +5. C) +6. D) +8. Show Answer Correct Answer: C) +6. 13. What do you call is the reaction that contains the element that is oxidized? A) Reagent. B) Reactant. C) Oxidant. D) Reductant. Show Answer Correct Answer: D) Reductant. 14. What is the oxidation state of silver in the reaction with silver diamine? A) 0. B) -1. C) +1. D) +2. Show Answer Correct Answer: C) +1. 15. The production of a diol using $OsO_4$ A) Syn addition. B) Anti addition. C) Markovnikov product. D) Anti-Markovnikov product. Show Answer Correct Answer: A) Syn addition. 16. What effect does temperature have on the voltage of a galvanic cell? A) Temperature has no effect on the voltage of a galvanic cell. B) Increasing the temperature increases the voltage of the cell. C) Decreasing the temperature increases the voltage of the cell. D) Increasing the temperature decreases the voltage of the cell. Show Answer Correct Answer: B) Increasing the temperature increases the voltage of the cell. 17. In the reaction, Fe$_{2}$O$_{3}$(s) + 3CO(g) $\rightarrow$ 2Fe(l) + 3CO$_{2}$(g) A) Carbon monoxide is reduced. B) Carbon monoxide is the oxidising agent. C) Iron(III) oxide is oxidised. D) Iron(III) oxide is the oxidising agent. Show Answer Correct Answer: D) Iron(III) oxide is the oxidising agent. 18. Reduction happens at the: A) Anode. B) Cathode. C) Salt bridge. D) Voltmeter. Show Answer Correct Answer: B) Cathode. 19. Which occurs in any voltaic cell (assuming metals involved in the reaction)? A) The cathode gets smaller. B) Electrode sizes don't change. C) The anode gets smaller. D) Both electrodes get bigger. Show Answer Correct Answer: C) The anode gets smaller. 20. What is the role of the salt bridge in a galvanic cell? A) To allow the flow of electrons between electrodes. B) To maintain electrical neutrality by allowing the flow of ions. C) To provide a surface for the redox reaction. D) To increase the voltage of the cell. Show Answer Correct Answer: B) To maintain electrical neutrality by allowing the flow of ions. 21. What is a common application of electrolysis? A) Cleaning surfaces. B) Generating heat. C) Extracting metals. D) Cooking food. Show Answer Correct Answer: C) Extracting metals. 22. Calculate the oxidation number of P in H$_{3}$P$_{2}$O$_{7 }$$^{-}$ A) +3. B) -5. C) +5. D) -3. Show Answer Correct Answer: C) +5. 23. What is oxidation state of oxygen in ozone (O3) molecule? A) -2. B) -1/2. C) 0. D) -1. Show Answer Correct Answer: C) 0. 24. In a voltaic cell electrons flow A) Through the salt bridge. B) From the cathode to the anode through the wire. C) From the anode to the cathode through the wire. D) None of the above. Show Answer Correct Answer: C) From the anode to the cathode through the wire. 25. What is the role of inert electrodes in a galvanic cell? A) To participate actively in the chemical reaction and get consumed. B) To provide a surface for the redox reaction without undergoing any chemical change themselves. C) To increase the electrical resistance of the cell. D) To act as a source of ions in the electrolyte solution. Show Answer Correct Answer: B) To provide a surface for the redox reaction without undergoing any chemical change themselves. ← 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