Q1. In the reaction \( \ce{2Cu2O + Cu2S -> 6Cu + SO2} \), which element is reduced?A. SulfurB. OxygenC. CopperD. None of these
Q4. Which of the following reactions does not involve a change in oxidation state?A. \( \ce{2H2 + O2 -> 2H2O} \)B. \( \ce{Cu + 2AgNO3 -> Cu(NO3)2 + 2Ag} \)C. \( \ce{KOH + HNO3 -> KNO3 + H2O} \)D. \( \ce{2FeCl2 + Cl2 -> 2FeCl3} \)
Q5. Which reaction involves a redox process where the oxidizing agent contains a halogen?A. \( \ce{2Na + O2 -> Na2O2} \)B. \( \ce{S + O2 -> SO2} \)C. \( \ce{2H2O2 -> 2H2O + O2} \)D. \( \ce{2Fe + 3I2 -> 2FeI3} \)
Q6. Which reaction involves a redox process where the reducing agent is a metal hydride?A. \( \ce{2Na + Cl2 -> 2NaCl} \)B. \( \ce{Fe + S -> FeS} \)C. \( \ce{2H2O2 -> 2H2O + O2} \)D. \( \ce{2NaH + O2 -> Na2O2 + H2} \)
Q7. What is the change in oxidation number of sulfur in the reaction \( \ce{S + 2H2SO4 -> 3SO2 + 2H2O} \)?A. +2B. +4C. +6D. -4
Q8. Which of the following is a redox reaction involving a metal?A. \( \ce{NaCl + AgNO3 -> AgCl + NaNO3} \)B. \( \ce{Ca(OH)2 + CO2 -> CaCO3 + H2O} \)C. \( \ce{NH3 + HCl -> NH4Cl} \)D. \( \ce{4Li + O2 -> 2Li2O} \)
Q9. Which reaction represents a displacement redox reaction?A. \( \ce{2Na + Cl2 -> 2NaCl} \)B. \( \ce{2H2O -> 2H2 + O2} \)C. \( \ce{Zn + CuSO4 -> ZnSO4 + Cu} \)D. \( \ce{2H2O2 -> 2H2O + O2} \)
Q10. What is the change in oxidation number of nitrogen in the reaction \( \ce{N2 -> 2NH3} \)?A. +3B. -3C. +6D. -6