redox a b

Question 1

Reduction

Answer 1

described a reaction in which oxygen was removed.

ln this reaction copper oxide has been reduced and hydrogen is the reducing agent.

Question 2

oxidised

Answer 2

When something is oxidised it loses

electrons,

Question 3

reduced

Answer 3

when something is reduced it gains electrons.

Question 4

redox reactions

Answer 4

Since redox reactions always involve the movement of electrons they are also called electron transfer reactions.

Question 5

reducing agents

Answer 5

give away electrons - they are electron donors

Question 6

oxidising

Answer 6

agents accept electrons.

Question 7

Oxidation states

Answer 7

are used to see what has been oxidised and what
has been reduced in a redox reaction.
Oxidation states are also called oxidation numbers.

Question 8

oxidation numbers.

Answer 8

are used to see what has been oxidised and what

has been reduced in a redox reaction.

Question 9

the oxidation state/numbers and electrons

Answer 9

tells us about the distribution of electrons between elements of different electronegativity. The more electronegative element is given the negative oxidation state.

Question 10

Every element in there og state

Answer 10

Every element in its uncombined state has an oxidation state of zero.

Question 11

hydrogen, H

Answer 11

+1

Question 12

group 1

Answer 12

+1

Question 13

group 2

Answer 13

+2

Question 14

aluminium

Answer 14

+3

Question 15

oxygen

Answer 15

-2

if peroxides it is -1
if in OF2 it will be +2

Question 16

fluorine

Answer 16

-1

Question 17

Cl

Answer 17

-1

Question 18

sum of all the oxidation states

Answer 18

The sum of all the oxidation states in a compound =0, since all
compounds are electrically neutral.

Question 19

SO24

Answer 19

ion has -2 charge
the charge of oygen = -2
suldur charge +6

Question 20

balancing half equations

Answer 20

balance atoms apart from h and o

add h20 to balance 0

balance h to balance h

balance e at the end