3. redox I (as)

Question 1

oxidation number tells you about

Answer 1

the movement of electrons

Question 2

oxidation number tells you

Answer 2

how many electrons an atom has donated or accepted to form an ion

Question 3

uncombined elements have the oxidation number

Answer 3

0

Question 4

what is the oxidation number of simple monatomic ions

Answer 4

same as its charge

Question 5

hydrogen oxidation number

Answer 5

+1 except in metal hydrides where it is -1

Question 6

oxygen oxidation number

Answer 6

-2 except in peroxides where it is -1

Question 7

redox reaction

Answer 7

where reduction ( gain of e) and oxidation ( loss of e) happen simultaneously

Question 8

what happens when an atom loses an electron

Answer 8

oxidation number will increase

Question 9

what happens when an atom gained an electron

Answer 9

oxidation number will decrease by 1

Question 10

if oxidation no increased
if oxidation no decreased

Answer 10

• lost e ,, oxidised
• gained e ,, reduced

Question 11

when metal form compounds they

Answer 11

donate e ,, form positive ions ,, oxidation no increase

Question 12

non metals form compounds they

Answer 12

generally gain e ,, form negative ions ,, oxidation no decreases

Question 13

disproportionation reaction

Answer 13

redox reaction where element in a single species is simultaneously oxidised and reduced

Question 14

reducing agent

Answer 14

element lost electrons and has been oxidised

Question 15

oxidising agent

Answer 15

element gained electrons and has been reduced