Oxidation, Reduction and Redox Reactions

Question 1

What is a Redox Reaction

Answer 1

A reaction in which both Oxidation and Reduction has occured

Question 2

what happens when a substance is reduced and what is it known as in terms of electrons

Answer 2

• gains electrons
• known as an electron acceptor/oxidising agent

Question 2

what happens when a substance is oxidised and what is it known as in terms of electrons

Answer 2

• loses electrons
• known as an electron donor/reducing agent

Question 3

what do oxidation states show

Answer 3

how many electrons the atom has used in bonding

Question 3

what does an decrease in oxidation state mean

Answer 3

• the substance has been reduced

Question 3

what does an increase in oxidation state mean

Answer 3

• the substance has been oxidised

Question 3

what is the oxidation state of an atom in an uncombined element

Answer 3

0

Question 3

what is the oxidation state of atoms in group 1,2,3

Answer 3

the amount of valence electrons on the atom

Question 3

what is the sum of oxidation states in neutral compounds

Answer 3

0

Question 4

what is the oxidation state of hydrogen in compounds

Answer 4

+1 except for metal hydrides where it is -1

Question 5

what is the oxidation state of oxygen in compounds

Answer 5

-2

one exception is in peroxides when it is -1

another exception is when combined with fluorine where it is also -1

Question 6

what is the sum of oxidation states in compound ions

Answer 6

equal to the charge on the ion