REDOX REACTION JEE

Given : XNa₂HAsO₃ +YNaBrO₃+ZHCl → NaBr + H₃AsO₄ + NaCl

The values of X, Y and Z in the above redox reaction are respectively :

• 2, 1, 3

• 3, 1, 6

• 2, 1, 2

• 3, 1, 4

Consider the following reaction:

xMnO₄^–+ yC₂O₄^2- +zH⁺ → xMn²⁺ + 2yCO₂+(z/2)H₂O

The values of x, y and z in the reaction are respectively :-

• 5, 2 and 16

• 2, 5 and 8

• 2, 5 and 16

• 5, 2 and 8

Consider the reaction

H₂SO₃(aq) + Sn⁴⁺(aq) + H₂O(l) → Sn²⁺(aq) + HSO₄^–(aq) + 3H⁺(aq)

Which of the following statements is correct?

• H₂SO₃ is the reducing agent because it undergoes oxidation

• H₂SO₃ is the reducing agent because it undergoes reduction

• Sn⁴⁺ is the reducing agent because it undergoes oxidation

• Sn⁴⁺ is the oxidizing agent because it undergoes oxidation

In which of the following reaction H₂O₂ acts as a reducing agent ?

(1) H₂O₂ + 2H⁺ + 2e^– → 2H₂O

(2) H₂O₂ -2e^– → O₂+2H⁺

(3) H₂O₂ + 2e^– → 2OH^–

(4) H₂O₂ + 2OH^– -2e^– → O₂ + 2H₂O

• (1), (3)

• (2), (4)

• (1), (2)

• (3), (4)

How many electrons are involved in the following redox reaction?

Cr₂O₇^2- + Fe²⁺ + C₂O₄^2- → Cr³⁺ + Fe³⁺ + CO₂ (Unbalanced)

• 3

• 4

• 5

• 6

Which of the following reactions is an example of a redox reaction ?

• XeF₄ + O₂F₂ → XeF₆ + O₂

• XeF₂ + PF₅ → [XeF]⁺ PF₆^–

• XeF₆ + H₂O → XeOF₄ + 2HF

• XeF₆ + 2H₂O → XeO₂F₂ + 4HF

Which of the following is a redox reaction ?

• NaCl + KNO₃ → NaNO₃ + KCl

• CaC₂O₄ + 2HCl → CaCl₂ + H₂C₂O

• Mg(OH)₂ + 2NH₄Cl → MgCl₂ + 2NH₄OH

• Zn + 2AgCN → 2Ag + Zn(CN)₂

When KMn0₄ acts as an oxidising agent and ultimately forms [MnO₄^2-, MnO_2, Mn₂O₃ and Mn⁺². Then the number of electrons trans­ferred in each case respectively is

• 4, 3, 1, 5

• 1, 5, 3, 7

• 1,3, 4, 5

• 3, 5, 7,1

For the redox reaction: Zn_(s) + Cu²⁺ (0.1 M)→ Zn⁺ (1M) + Cu_(s) taking place in a cell, E°cell is 1.10 volt. E_cell for the cell will be (2.303 RT / F = 0.0591)

• 2.14 V

• 1.80 V

• 1.07 V

• 0.82 V

What would happen when a solution of potassium chromate is treated with an excess of dilute nitric acid?

• Cr₂O₇^2- and H₂O are formed

• Cr₂O₇^2- is reduced to +3 state of Cr

• Cr₂O₇^2- is oxidises to +7 state of Cr

• Cr³⁺ and Cr₂O₇^2- are formed