Redox Reactions

Question 1

When do redox reactions occur?

Answer 1

When electrons are transferred from the atom that becomes oxidised to the atom that becomes reduced

Question 2

What is oxidation?

Answer 2

Loss of electrons, becoming + charged

Question 3

What is reduction?

Answer 3

Gain of electrons, becoming - charged

Question 4

What is the oxidation state?

Answer 4

Either the actual chan=rage of the monoatomic ion, or a hypothetical charge assigned to the atom

Question 5

What is the oxidation number for an atom in its elemental form?

Answer 5

0

Question 6

What is the oxidation number for any monatomic ion?

Answer 6

Equal to the charge of the ion, e.g Na+ = +1

Question 7

What is the oxidation number for nonmetals?

Answer 7

Usually have negative oxidation numbers , e.g. oxygen = -2 but hydrogen = +1

Question 8

What is the oxidation number in neutral compounds?

Answer 8

0

Question 9

What is the oxidation number for fluorine?

Answer 9

-1

Question 10

What’s the oxidation number for group 1 elements?

Answer 10

+1

Question 11

What is the oxidation number for group 2 elements?

Answer 11

+2

Question 12

What is the oxidation number for hydrogen with nonmetals?

Answer 12

+1

Question 13

What is the oxidation number for hydrogen with metals?

Answer 13

-1

Question 14

What are the 2 exceptions for oxygens oxidation number?

Answer 14

When bound to fluorine or in a peroxide

Question 15

In oxidation half reactions, where are electrons presented?

Answer 15

As the products

Question 16

In reduction half reactions, how are electrons presented?

Answer 16

As reactants

Question 17

How do you balance equations by the method of half reactions?

Answer 17

1- Assign oxidation states (who is gaining e- and who is losing e-)
2- Divide the reaction into 2 half reactions
3- Balance each half reactions
4- Multiply the half reactions by whole numbers
5- Add 2 half reactions together and simplify