Identify the oxidant and reductant in each reaction

Question

I just need question 15, thank you!

14. Balance each reaction below, and write a cell schematic representing the reaction as it would occur in a galvanic cell.

(a) Al(𝑠)+Zr4+(𝑎𝑞)⟶Al3+(𝑎𝑞)+Zr(𝑠)Al(s)+Zr4+(aq)⟶Al3+(aq)+Zr(s)

(b) Ag+(𝑎𝑞)+NO(𝑔)⟶Ag(𝑠)+NO3−(𝑎𝑞)(acidic solution)Ag+(aq)+NO(g)⟶Ag(s)+NO3−(aq)(acidic solution)

(c) SiO32−(𝑎𝑞)+Mg(𝑠)⟶Si(𝑠)+Mg(OH)2(𝑠)(basic solution)SiO32−(aq)+Mg(s)⟶Si(s)+Mg(OH)2(s)(basic solution)

(d) ClO3−(𝑎𝑞)+MnO2(𝑠)⟶Cl−(𝑎𝑞)+MnO4−(𝑎𝑞)(basic solution)ClO3−(aq)+MnO2(s)⟶Cl−(aq)+MnO4−(aq)(basic solution)

15. Identify the oxidant and reductant in each reaction of the previous exercise.

Answer 1

Here's the rest from your other question:

(a) SO₃²⁻(𝑎𝑞)+Cu(OH)₂(𝑠) ⟶ SO₄²⁻(aq) + Cu(OH)(s)

To balance oxygens, add H2O:

SO₃^2- + H₂O ===> SO₄^2- 

Cu(OH)2 ===> CuOH + H₂O

To balance hydrogens add H⁺:

SO₃^2- + H₂O ===> SO₄^2- + 2H⁺

Cu(OH)2 + H⁺ ===> CuOH + H₂O

To convert to basic solution, add OH^- where ever you added H⁺ and add it to both sides:

SO₃^2- + H₂O + 2OH^- ===> SO₄^2- + 2H⁺ + 2OH^-

Cu(OH)2 + H⁺ + OH^- ===> CuOH + H₂O + OH^-

Where possible, combine H+ and OH- to make H₂O:

SO₃^2- + H₂O + 2OH^- ===> SO₄^2- + 2H2O

Cu(OH)2 + H2O ===> CuOH + H₂O + OH^-

Add electrons to balance the charge:

SO₃^2- + H₂O + 2OH^- ===> SO₄^2- + 2H2O + 2e-

Cu(OH)2 + H2O + 1e- ===> CuOH + H₂O + OH^-

Multiply 2nd equation by 2 to equalize electrons:

SO₃^2- + H₂O + 2OH^- ===> SO₄^2- + 2H2O + 2e-

2Cu(OH)2 + 2H2O + 2e- ===> 2CuOH + 2H₂O + 2OH^-

Add the two equations together:

SO₃^2- + H₂O + 2OH^- + 2Cu(OH)2 + 2H2O + 2e- ==> SO₄^2- + 2H2O + 2e- + 2CuOH + 2H₂O + 2OH^-

Combine terms and cancel where appropriate:

SO₃^2- + 2Cu(OH)₂ ===> SO₄^2- + H₂O + 2CuOH ... balanced equation in basic solution