This quiz works best with JavaScript enabled. Home > Class 11 > Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions – Quiz 5 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 5 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Which salt will be produced if magnesium react with hydrochloric acid? A) Magnesium oxide. B) Magnesium sulfate. C) Magnesium sulfide. D) Magnesium chloride. Show Answer Correct Answer: D) Magnesium chloride. 2. Define reduction. A) Gain of electron. B) Loss of electron. C) All the above. D) None of the above. Show Answer Correct Answer: A) Gain of electron. 3. Which of the following cannot occur during oxidation? A) Gain of oxygen. B) Donation of electrons. C) Loss of hydrogen. D) Decrease in oxidation number. Show Answer Correct Answer: D) Decrease in oxidation number. 4. What are the oxidation numbers of sodium and iodine in potassium triiodide, KI$_{3}$? A) K = +1; I = 0. B) K = +1; I =-1. C) K =-1; I =-3. D) K = +1; I =-1/3. E) K = +1; I =-2/3. Show Answer Correct Answer: D) K = +1; I =-1/3. 5. Hydrogen sulfide gas is bubbled through a solution of potassium hydroxide; what is the net ion equation? A) H$^{+}$ + OH$^{-}$$\rightarrow$ H$_{2}$O. B) H$_{2}$S + OH$^{-}$ $\rightarrow$ H$_{2}$O + S$^{2-}$. C) No rxn. D) H$_{2}$S + KOH $\rightarrow$H$_{2}$O + K$_{2}$S. Show Answer Correct Answer: B) H$_{2}$S + OH$^{-}$ $\rightarrow$ H$_{2}$O + S$^{2-}$. 6. What is the oxidation number of the chromium element in potassium dichromate (VI), $K_2Cr_2O_7$ A) +2. B) +3. C) +5. D) +6. Show Answer Correct Answer: D) +6. 7. What is the role of electrons in redox reactions? A) Electrons are solely responsible for heat generation. B) Electrons are not involved in chemical reactions. C) Electrons are only involved in ionic bonding. D) Electrons are transferred between reactants. Show Answer Correct Answer: D) Electrons are transferred between reactants. 8. Which of these chemical reactions is an oxidation-reduction reaction? A) CO$_{2}$ + H$_{2}$O $\rightarrow$ H$_{2}$CO$_{3}$. B) Fe + S $\rightarrow$ FeS. C) AgNO$_{3}$ + NaCl $\rightarrow$AgCl + NaNO$_{3}$. D) H$_{2}$SO$_{4}$ + 2NaOH $\rightarrow$ Na$_{2}$SO$_{4}$ + 2H$_{2}$O. Show Answer Correct Answer: B) Fe + S $\rightarrow$ FeS. 9. How are electrons treated in the balancing of redox equations? A) Only considered in acid-base reactions. B) Assumed to be lost in the reaction. C) Counted to ensure the same number on both sides of the equation. D) Ignored, as they are not important. Show Answer Correct Answer: C) Counted to ensure the same number on both sides of the equation. 10. Product of electrolysis:An aqueous solution of silver nitrate with platinum electrodes A) Anode:AgCathode:NO$_{3}$. B) Anode:NO$_{3}$Cathode:Ag. C) Anode:O$_{2}$Cathode:Ag. D) None of these. Show Answer Correct Answer: C) Anode:O$_{2}$Cathode:Ag. 11. What is the anode in a galvanic cell? A) The electrode where oxidation occurs. B) The electrode where reduction occurs. C) The electrode that attracts cations. D) The electrode that attracts anions. Show Answer Correct Answer: A) The electrode where oxidation occurs. 12. Oxidation number of any free element is always ..... A) 0. B) 1. C) 2. D) 3. Show Answer Correct Answer: A) 0. 13. 2Pb(NO$_{3}$)$_{2}$ $\rightarrow$ 2PbO + 4NO$_{2}$ + O$_{2}$ A) Synthesis. B) Decomposition. C) Single Displacement. D) Combustion. Show Answer Correct Answer: B) Decomposition. 14. Which of the following is a characteristic feature of a redox reaction? A) It involves the exchange of protons between reactants. B) It only occurs in basic solutions. C) It involves the transfer of electrons between reactants. D) It results in the formation of a precipitate. Show Answer Correct Answer: C) It involves the transfer of electrons between reactants. 15. What happens to the oxidation number of an element that is reduced? A) The oxidation number increases. B) The oxidation number remains the same. C) The oxidation number decreases. D) The oxidation number fluctuates. Show Answer Correct Answer: C) The oxidation number decreases. 16. In the reaction 2H$_{2}$ + O$_{2}$ $\rightarrow$ 2H$_{2}$O, which element is reduced? A) Hydrogen. B) Oxygen. C) Both. D) None. Show Answer Correct Answer: B) Oxygen. 17. What is the stoichiometry of KMnO4 in a titration with Fe2+? A) 1:4. B) 1:3. C) 1:5. D) 1:6. Show Answer Correct Answer: C) 1:5. 18. In a redox reaction, one substance gets oxidised while other gets A) Oxidised. B) Neutralised. C) Reduced. D) Combined. Show Answer Correct Answer: C) Reduced. 19. Which half-reaction correctly represents reduction reaction? A) Br$^{-}$+ 2e$^{-}$ $\rightarrow$Br$_{2}$. B) Mn$^{2+}$ + e$^{-}$ $\rightarrow$Mn. C) Ag$^{+}$ + 2e$^{-}$ $\rightarrow$Ag. D) Cu$^{2+}$ + 2e$^{-}$ $\rightarrow$Cu. Show Answer Correct Answer: D) Cu$^{2+}$ + 2e$^{-}$ $\rightarrow$Cu. 20. How does the oxidation state of Li change in the following reaction?Li(s) + NaOH(aq) $\rightarrow$ LiOH(aq) + Na(s) A) It goes from 0 to-1. B) It goes from +1 to +2. C) It goes from 0 to +1. D) It does not change. Show Answer Correct Answer: C) It goes from 0 to +1. 21. What coefficient would Fe$^{+2}$ have in the following reaction? ..... Al + ..... Fe$^{+2}$ $\rightarrow$ ..... Al$^{+3}$ + ..... Fe A) 1. B) 2. C) 3. D) 6. Show Answer Correct Answer: C) 3. 22. What is the oxidation state of hydrogen in compounds? A) -1. B) 0. C) +1. D) +2. Show Answer Correct Answer: C) +1. 23. What is the oxidation number of hydrogen in MgH$_{2}$? A) -1. B) +1. C) -2. D) +2. Show Answer Correct Answer: A) -1. 24. Which component is not part of a basic fuel cell? A) Anode. B) Cathode. C) Salt bridge. D) Electrolyte. Show Answer Correct Answer: C) Salt bridge. 25. Which of the following represents oxidation? A) C $\rightarrow$ CH$_{4}$. B) Fe$^{3+}$ $\rightarrow$ Fe$^{2+}$. C) Cl$_{2}$ $\rightarrow$ 2Cl$^{-}$. D) Zn $\rightarrow$ ZnO. Show Answer Correct Answer: D) Zn $\rightarrow$ ZnO. ← 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 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 10Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 11 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books