Answer:
A. The correct option is: Cu; H₂SO₄; H₂SO₄; Cu
B. The correct option is: SO₂; HNO₃; HNO₃; SO₂
C. The correct option is: Zn; H₂SO₄; H₂SO₄; Zn
D. The correct option is: I₂; HNO₃; HNO₃; I₂
Explanation:
A chemical reaction that involves the simultaneous transfer of electrons between two chemical species is known as the redox reaction.
In this reaction, a species that gains electrons, thus getting reduced is called the <u>oxidizing agen</u>t. Whereas, species that loses electrons, thus getting oxidized is called the<u> reducing agent</u>.
<u>Oxidation</u> refers to an increase in the oxidation state and <u>reduction</u> refers to a decrease in the oxidation state.
A. Cu + 2H₂SO₄ → CuSO₄ + SO₂ +2H₂O
In this reaction, Cu goes from 0 in Cu to +4 oxidation state in CuSO₄ and thus gets oxidized. Whereas, S goes from +6 in H₂SO₄ to +4 oxidation state in SO₂ and thus gets reduced. Therefore, H₂SO₄ is the oxidizing agent and Cu is the reducing agent.
<u>The correct option is: Cu; H₂SO₄; H₂SO₄; Cu</u>
B. 3SO₂ + 2HNO₃ + 2H₂O → 3H₂SO₄ + 2NO
In this reaction, S goes from +4 in SO₂ to +6 oxidation state in H₂SO₄ and thus gets oxidized. Whereas, N goes from +5 in HNO₃ to +2 oxidation state in NO and thus gets reduced. Therefore, HNO₃ is the oxidizing agent and SO₂ is the reducing agent.
<u>The correct option is: SO₂; HNO₃; HNO₃; SO₂</u>
C. 5H₂SO₄ + 4Zn → 4ZnSO₄ + H₂S +4H₂O
In this reaction, Zn goes from 0 in Cu to +2 oxidation state in ZnSO₄ and thus gets oxidized. Whereas, S goes from +6 in H₂SO₄ to -2 oxidation state in H₂S and thus gets reduced. Therefore, H₂SO₄ is the oxidizing agent and Zn is the reducing agent.
<u>The correct option is: Zn; H₂SO₄; H₂SO₄; Zn</u>
D. I₂ + 10HNO₃ → 2HIO₃ + 10NO₂ + 4H₂O
In this reaction, I goes from 0 in I₂ to +5 oxidation state in HIO₃ and thus gets oxidized. Whereas, N goes from +5 in HNO₃ to +4 oxidation state in NO₂ and thus gets reduced. Therefore, HNO₃ is the oxidizing agent and I₂ is the reducing agent.
<u>The correct option is: I₂; HNO₃; HNO₃; I₂</u>