chemical reactions-oxidation,reduction,corrosion,rancidity

Oxidation involves:

• A)Gain of hydrogen
• B) Loss of oxygen
• C) Loss of hydrogen
• D) Loss of electrons

In a redox reaction, the substance that gets reduced:

• A)Loses electrons
• B) Gains electrons
• C) Loses oxygen
• D) Gains hydrogen

Which of the following is an example of oxidation?

• A)Cl₂ → 2Cl⁻
• B) Fe²⁺ → Fe³⁺
• C) Cu²⁺ → Cu
• D) H₂ → 2H⁺

Which statement is correct for a redox reaction?

• A)Both oxidation and reduction occur separately
• B) Only oxidation occurs
• C) Oxidation and reduction occur simultaneously
• D) Only reduction occurs

In the reaction: Zn + CuSO₄ → ZnSO₄ + Cu, the reducing agent is:

• A)Zn
• B) Cu
• C) Cu²⁺
• D) SO₄²⁻

What happens to the oxidation number of a substance when it is oxidized?

• A)Decreases
• B) Increases
• C) Remains same
• D) Doubles

Which reaction shows reduction?

• A)Fe → Fe²⁺
• B) Cu → Cu²⁺
• C) O₂ → 2O²⁻
• D) H₂O → H₂

What is the oxidizing agent in the reaction 2H₂ + O₂ → 2H₂O

• A)H₂
• B) O₂
• C) H₂O
• D) None

In the redox reaction, the species which donates electrons is:

• A)Oxidising agent
• B) Reducing agent
• C) Catalyst
• D) Neutral

Which is NOT true about redox reactions?

• A)Always involve transfer of electrons
• B) Always involve change in oxidation states
• C) Only occur in aqueous solutions
• D) Involve oxidation and reduction together