Balancing Redox Reaction Video Lessons

Video Thumbnail

Concept

Problem: 2 NO3-(aq) + 8 H+(aq) + 3 Cu(s) → 2 NO(g) + 4 H2O(l) + 3 Cu2+(aq)1) Indicate the half-reaction occurring at Anode.Express your answer as a chemical equation. Identify all of the phases in your answer.2) Indicate the half-reaction occurring at Cathode.Express your answer as a chemical equation. Identify all of the phases in your answer.

FREE Expert Solution

2 NO3-(aq) + 8 H+(aq) + 3 Cu(s) → 2 NO(g) + 4 H2O(l) + 3 Cu2+(aq)


Step 1. Separate the whole reaction into half-reactions

*ignore H2O(l) and H+

NO3-(aq) → NO(g)

Cu(s) → Cu2+(aq)


Step 2. Balance the non-hydrogen and non-oxygen elements first

NO3-(aq) → NO(g)

Cu(s) → Cu2+(aq)


Step 3. Balance oxygen by adding H2O to the side that needs oxygen (1 O: 1 H2O)

NO3-(aq) → NO(g) + 2 H2O(l)

Cu(s) → Cu2+(aq)


Step 4. Balance hydrogen by adding H+ to the side that needs hydrogen (1 H: 1 H+)

NO3-(aq) + 4 H+(aq) → NO(g) + 2 H2O(l)

Cu(s) → Cu2+(aq)


Step 5. Balance the charges: add electrons to the more positive side (or less negative side)

NO3-(aq) + 4 H+(aq) + 3 e → NO(g) + 2 H2O(l)

Cu(s) → Cu2+(aq) + 2 e


Step 6. Balance electrons on the two half-reactions

[ NO3-(aq) + 4 H+(aq) + 3 e → NO(g) + 2 H2O(l) ] x 2

Cu(s) → Cu2+(aq) + 2 e ] x 3


2 NO3-(aq) + 8 H+(aq) + 6 e → 2 NO(g) + 4 H2O(l)

                                  3 Cu(s) → 3 Cu2+(aq) + 6 e
 _______________________________________________________

2 NO3-(aq) + 3 Cu(s) + 8 H+(aq) → 2 NO(g) + 3 Cu2+(aq) + 4 H2O(l)



Step 4. Determine the oxidation half-reaction and the reduction half-reaction. 

80% (293 ratings)
View Complete Written Solution
Problem Details

2 NO3-(aq) + 8 H+(aq) + 3 Cu(s) → 2 NO(g) + 4 H2O(l) + 3 Cu2+(aq)

1) Indicate the half-reaction occurring at Anode.

Express your answer as a chemical equation. Identify all of the phases in your answer.

2) Indicate the half-reaction occurring at Cathode.

Express your answer as a chemical equation. Identify all of the phases in your answer.

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Balancing Redox Reaction concept. You can view video lessons to learn Balancing Redox Reaction. Or if you need more Balancing Redox Reaction practice, you can also practice Balancing Redox Reaction practice problems.