Redox

Question 1

What is oxidation?

Answer 1

• loss of electrons

- oxidation state increases

Question 2

What is reduction?

Answer 2

• gain of electron

- oxidation state decreases

Question 3

What is an oxidising agent?

Answer 3

• gains electrons from other species

- oxidising agent itself is reduced

Question 4

What is an reducing agent?

Answer 4

• loses electrons to give it to other species

- is itself oxidised

Question 5

What is the oxidation state of hydrogen?

Answer 5

• always +1

- except in metal hydrides, where is -1 e.g. NaH

Question 6

What is the oxidation state of group 1 metals?

Answer 6

Always +1

Question 7

What is the oxidation state of group 2 metals?

Answer 7

Always +2

Question 8

What is the oxidation state of Aluminium?

Answer 8

Always +3

Question 9

What is the oxidation state of oxygen?

Answer 9

-2, EXCEPT when with peroxide compound e.g. H2O2 or bonded to F then it will be -1

Question 10

What is the oxidation state of Chlorine?

Answer 10

-1, EXCEPT in compounds containing F or O where it can have a positive value

Question 11

What is the oxidation state of uncombined elements?

Answer 11

ALWAYS 0

Question 12

How would you balance out a REDOX half equation?

Answer 12

• Balance central ion/atom (not O or H)
• Balance O (if present) with water molecules
• Balance the H by adding H+ ions
• Balance charges by adding adding electron on the more positive side

Question 13

What is a disproportionation reaction?

Answer 13

Same element undergoes oxidation and reduction at the same time