topic 3

Question 1

oxidation

Answer 1

loss of electrons
increase in oxidation number

Question 2

reduction

Answer 2

gain of electrons
decrease in oxidation number

Question 3

rules for assigning oxidation number

Answer 3

• all uncombined elements have an oxidation number of zero (O2, Cl2, Zn)
  
  • oxidation number of elements in a compound add up to zero
  • oxidation number of monoatomic ion is equal to its ionic charge (Zn2+)

Question 4

oxidation number of common compounds

Answer 4

group 1 metals = +1
group 2 metals = +2
Al = +3
H = +1
F = -1
Cl, Br, I = -1
O = -2

Question 5

reducing agents

Answer 5

electron donors

Question 6

oxidising agents

Answer 6

electron acceptors

Question 7

redox reactions

Answer 7

reactions where both oxidation and reduction are taking place

Question 8

disproportionation

Answer 8

reaction where an element in a single species simultaneously oxidises and reduces