This quiz works best with JavaScript enabled. Home > Class 11 > Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions – Quiz 30 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 11 Chemistry (Part Ii) Chapter 8 Redox Reactions Quiz 30 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. In the following reaction:2CuO (s) + C (s) $\rightarrow$ 2Cu (s) + CO$_{2}$ (g)What undergoes oxidation? A) Copper (Cu). B) Carbon (C). C) Copper ions (Cu$^{2+}$). D) Carbon dioxide (CO$_{2}$). Show Answer Correct Answer: B) Carbon (C). 2. Oxidation occurs when a substance gain electrons A) TRUE. B) FALSE. C) All the above. D) None of the above. Show Answer Correct Answer: B) FALSE. 3. It is when an atom's oxidation state increases during a reaction. A) Oxidation. B) Reduction. C) Reduction-oxidation reaction. D) None of the given choices. Show Answer Correct Answer: A) Oxidation. 4. What is occurring in this reaction 2Mg$_{(s)}$ + O$_{2(g)}$ $\rightarrow$ 2MgO$_{(s)}$? A) Oxygen atom displaces the magnesium atoms. B) A solid magnesium ribbon is undergoing reduction while oxygen is undergoing oxidation. C) A solid magnesium ribbon is undergoing oxidation while oxygen is undergoing reduction. D) A transfer of electrons from oxygen to magnesium. Show Answer Correct Answer: C) A solid magnesium ribbon is undergoing oxidation while oxygen is undergoing reduction. 5. The sum of the oxidation numbers in SCN$^{-}$ is equivalent to A) 0. B) -1. C) +1. D) +3. Show Answer Correct Answer: B) -1. 6. If an atom lost electrons, it ..... A) Was burned. B) Was reduced. C) Was oxidized. D) It became negative. Show Answer Correct Answer: C) Was oxidized. 7. Is Zn$^{2+}$ an oxidizing agent or reducing agent? A) Oxidizing agent. B) Reducing agent. C) Neither. D) Both. Show Answer Correct Answer: A) Oxidizing agent. 8. A redox reaction is a chemical reaction where ..... A) Oxidation occurs. B) Reduction occurs. C) Oxidation and reduction occurs simultaneously. D) Oxidation occur followed by reduction. Show Answer Correct Answer: C) Oxidation and reduction occurs simultaneously. 9. Corrosion, a type of redox reaction, can cause cars and buildings to rust. Rusting happens when iron is oxidized by oxygen in the air. This process happens when ..... A) Oxygen acts as the reducing agent and gains electrons. B) Iron acts as the reducing agent and loses electrons. C) Oxygen acts as the oxidizing agent and loses electrons. D) Iron acts as the oxidizing agent and gains electrons. Show Answer Correct Answer: B) Iron acts as the reducing agent and loses electrons. 10. In the reaction $\text{2H}_2 + \text{O}_2 \rightarrow 2\text{H}_2\text{O}$ A) Hydrogen ( $\text{H}_2$. B) Oxygen ( $\text{O}_2$. C) Water ( $\text{H}_2\text{O}$. D) None. Show Answer Correct Answer: B) Oxygen ( $\text{O}_2$. 11. Which change indicates oxidation? A) Sn$^{4+}$ becomes Sn$^{2+}$. B) Cr$^{3+}$ becomes Cr$^{6+}$. C) Fe$^{3+}$ becomes Fe. D) None of the above. Show Answer Correct Answer: B) Cr$^{3+}$ becomes Cr$^{6+}$. 12. In the reaction 2H2 + O2 $\rightarrow$ 2H2O, what is the oxidation state of hydrogen in water? A) +1. B) +2. C) 0. D) -1. Show Answer Correct Answer: A) +1. 13. Which of the following would not increase the amount of a metal being electroplated? A) Increasing the current. B) Increasing the time of electrolysis. C) Increasing the charge of the ion. D) Increasing the solution concentration. Show Answer Correct Answer: C) Increasing the charge of the ion. 14. What is the reducing agent of this reaction?3Mg + N$_{2}$$\rightarrow$ Mg$_{3}$N$_{2}$ A) Mg. B) N$_{2}$. C) Mg$_{3}$N$_{2}$. D) MgN. Show Answer Correct Answer: A) Mg. 15. Which is false about redox reactions? A) Involve a transfer of electrons. B) Losing electrons is oxidation. C) The oxidizing agent increases its oxidation state. D) Include single replacement reactions. Show Answer Correct Answer: C) The oxidizing agent increases its oxidation state. 16. Identify the oxidizing and reducing agents in the reaction:2Mg + O2 $\rightarrow$ 2MgO. A) Reducing agent:Mg, Oxidizing agent:O2. B) Reducing agent:MgO, Oxidizing agent:O2. C) Reducing agent:O2, Oxidizing agent:Mg. D) Reducing agent:O2, Oxidizing agent:MgO. Show Answer Correct Answer: A) Reducing agent:Mg, Oxidizing agent:O2. 17. What type of redox reaction involves the transfer of electrons between two species? A) Synthesis reaction. B) Decomposition reaction. C) Oxidation-reduction reaction. D) Combustion reaction. Show Answer Correct Answer: C) Oxidation-reduction reaction. 18. For redox reactions, half equations show A) Electrons loss and gain for each element, and together they show the complete redox reaction. B) Show transfer of electrons without any change in oxidation states. C) Spectator ions and how they lose and gain electrons. D) Show the complete reaction without needing to consider oxidation or reduction. Show Answer Correct Answer: A) Electrons loss and gain for each element, and together they show the complete redox reaction. 19. The S atom is in group 16 in periodic table and its theoritical maximum oxidation state is ..... A) -2. B) +2. C) +4. D) +6. Show Answer Correct Answer: D) +6. 20. When a metal compound reacts with a more reactive metal, what sort of reaction occurs? A) Displacement. B) Neutralisation. C) Combustion. D) No Reaction. Show Answer Correct Answer: A) Displacement. 21. What is a cation? A) A negatively charged ion that has gained one or more electrons. B) A positively charged ion that has lost one or more electrons. C) A neutral atom with no charge. D) A type of molecule that contains both positive and negative charges. Show Answer Correct Answer: B) A positively charged ion that has lost one or more electrons. 22. These keep track of the movement of electrons. A) (+) and (-) signs. B) Oxidation numbers. C) Coefficients. D) Subscripts. Show Answer Correct Answer: B) Oxidation numbers. 23. Which statement is true of a reducing agent? A) It is oxidised as it gains electrons. B) It is oxidised as it loses electrons. C) It is reduced as it gains electrons. D) It is reduced as it loses electrons. Show Answer Correct Answer: B) It is oxidised as it loses electrons. 24. In displacement reactions, what happens when a more reactive metal is added to a solution of a less reactive metal compound? A) The more reactive metal displaces the less reactive metal. B) The less reactive metal displaces the more reactive metal. C) No reaction occurs. D) Both metals form a new compound. Show Answer Correct Answer: A) The more reactive metal displaces the less reactive metal. 25. What is the effect of pH on the reduction potential of Cr in dichromate? A) The reduction potential of Cr in dichromate is unaffected by pH. B) The reduction potential of Cr in dichromate is higher in alkaline conditions. C) The reduction potential of Cr in dichromate increases in acidic conditions and decreases in alkaline conditions. D) The reduction potential of Cr in dichromate decreases in acidic conditions. Show Answer Correct Answer: C) The reduction potential of Cr in dichromate increases in acidic conditions and decreases in alkaline conditions. ← 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