Oxidation-Reduction

Question 1

oxidation

Answer 1

when atoms lose electrons

Question 2

reduction

Answer 2

when an atom gains electrons

Question 3

balancing simple redox (6)

Answer 3

1. write half reactions for the oxidized and reduced species
2. balance elements with coefficients
3. balance electric charges by adding coefficients to the side with the greatest charge
4. equalize and cancel the electrons
5. combine the half reactions
6. cancel like terms, reduce, and check

Question 4

oxidation number

Answer 4

the charge an atom has when all bonds are assumed to be ionic

Question 5

balancing redox equations with oxygen and/or hydrogen in an acidic solution (8)

Answer 5

1. write half reactions for both oxidized and reduced
2. balance all elements with coefficients except hydrogen and oxygen
3. balance oxygen by adding water molecules
4. balance hydrogen by adding H+ ions
5. balance the electric charges by adding electrons
6. equalize and cancel the electrons
7. combine the half reactions
8. cancel like terms, reduce, and check

Question 6

balancing redox equations with oxygen and/or hydrogen in an acidic solution (10)

Answer 6

1. write half reactions
2. balance all atoms except hydrogen and oxygen
3. balance the oxygen by adding water
4. balance the hydrogen with the hydrogen ions
5. balance the hydrogen ions by adding water hydroxide ions to both sides
6. combine the hydrogen ions and the hydroxide ions to form water molecules
7. balance the electric charges by adding electrons
8. equalize and cancel the electrons
9. combine half reactions
10. reduce, cancel like terms, and check