1. A standard reduction electrode potentials of four metals are A = -0.250 V, B = -0.140 V, C = -0.126 V, D = -0.402 V The metal that displaces A from its aqueous solution is:

2. When KMnO₄ acts as an oxidising agent and ultimately forms MnO2−4, MnO₂, Mn₂O₃ and Mn²⁺ then the no. of electrons transferred in each case respectively is

3. Find the redox reaction

4. The oxidation number of sulphur in S₈, S₂F₂, H₂S respectively are

5. The colourless solution of silver nitrate slowly turns blue on adding copper chips to it because of

6. Which of the following is a redox reaction?

7. KMnO₄​ reacts with oxalic acid according to the equation 2MnO₄^–​ + 5C₂​O₄​^2-​ + 16H+ → 2Mn²⁺​ +10CO₂​ + 8H₂​O Here 20 mL of 0.1 M KMnO₄​ is equivalent to

8. Metals generally react with dilute acids to produce hydrogen gas. Which one of the following metals does not react with dilute hydrochloric acid?

9. What is n-factor?

10. The oxidation number of Xe in BaXeO₆ is

11. Find the oxidation state of I in H₄IO₆^–

12. Which of the following processes does not involve oxidation of iron?

13. How many millilitres of 0.5 M H₂SO₄ are needed to dissolve 0.5 g of copper(II)carbonate?

14. During a reaction of oxalic acid, potassium chlorate and sulphuric acid, the oxidation number of which of the element undergoes a maximum change

15. One mole of N₂H₄ loses ten moles of electrons to form a new compound A. Assuming that all the nitrogen appears in the new compound, what is the oxidation state of nitrogen in A? (There is no change in the oxidation state of hydrogen.)

16. The number of moles of KMnO4 reduced by one mole of KI in alkaline medium is

17. The oxidation number of Mn is maximum in

18. H₂O₂ changes Cr₂O₇^2- ion to CrO₅ in an acidic medium, the oxidation state of Cr in CrO₅ is

19. One mole of ferrous oxalate requires____ moles of MnO₄^– to get oxidised completely in an acidic medium

20. Which among the following is the strongest oxidising agent?