redox reactions

Question 1

describe oxidation

Answer 1

oxidation is the gain of oxygen atoms, loss of hydrogen atoms, loss of electrons and an increase in the oxidation state number

Question 2

describe reduction

Answer 2

reduction is the loss of oxygen atoms, gain of hydrogen atoms, gain of electrons and a decrease in the oxidation state number

Question 3

what is a disproportionation reaction?

Answer 3

it is a redox reaction in which one species is simultaneously reduced and oxidised

Question 4

how to balance redox equations under an acidic medium?

Answer 4

1. identify species getting oxidised or reduced
2. balance the elements
3. balance oxygen atoms by adding H2O
4. balance hydrogen atoms by adding H+
5. balance overall charges by adding electrons
6. ensure that the electrons on both half equations are balanced
7. eliminate any common species on both sides

Question 5

how to balance an equation under an alkaline medium?

Answer 5

1. identify species getting oxidised or reduced
2. balance the elements
3. balance oxygen atoms by adding H2O
4. balance hydrogen atoms by adding H+
5. balance overall charges by adding electrons
6. remove H+ by adding OH-
7. combine H+ with OH- to form H2O
8. remove any species that appears on both sides
9. multiply such that the electrons in both half-equations are the right number
10. remove any common species on both sides