aqueous ions

Question 1

Lewis base

Answer 1

electron pair donator

Question 2

Lewis acid

Answer 2

electron pair acceptor

Question 3

bronsted Lowry acid

Answer 3

proton donor

Question 4

bronzed Lowry base

Answer 4

proton accept

Question 5

in the formation of metal ions what is the Lewis base and Lewis acid

Answer 5

Lewis base is the ligand as it donating a pair of electrons and the metal ion in the Lewis acid as its accepting a pair of electrons

Question 6

where are metal aqua ions formed

Answer 6

in an aqueous solution (when we add transition metal to water)

Question 7

Fe 2+ (FeII) aqueous ion structure and colour

Answer 7

[Fe(H2O)6]2+ it is green solution

Question 8

Copper(II) 2+ aqueous ion structure and colour

Answer 8

[Cu(H2O)6]2+
blue solution

Question 9

Iron(III) 3+ aqueous ion structure and colour????

Answer 9

[Fe(H2O)6]3+(aq) purple solution
may look yellow- brown due to some [Fe(H2O)5(OH)]2+(aq)

Question 10

Aluminium(III) 3+ aqueous ion structure and colour

Answer 10

[Al(H2O)6]3+(aq) colourless solution

Question 11

in solution are metal aqua ions acidic or basic (when metal aqua ions react with water)

Answer 11

they are acidic because they donate a H+ to water to form hydronium ion

Question 12

how does the charge change when metal aqua ion react with water

Answer 12

they form a hydroxide ion which is minus one so the charge goes down by one

Question 13

what type of reaction is the metal aqua ion and water

Answer 13

it is a hydrolysis reaction because part of a the aqua ion has been broken off due to a reaction with water

Question 14

why does the charge of an ion effect how acidic it is (how easily it dissociates to form the hydronium ion)

Answer 14

-a higher charge density means that they are more polarising. This means the attract the electrons in an O-H bond in one of the ligands more strongly. This weakens that bond. This makes it more likely that a H+ ion will be released when its dissolved in solution. Hence why a higher charge density means that it will dissociate more easily.

Question 15

how does the equilibrium change when you add more OH-

Answer 15

the equilibrium shifts to the right as the OH- will react with hydronium ions and so you will need to produce more. The acid will carry on dissociating until it reaches a neutral complex which is solid.

Question 16

Iron(II) neutral complex with NaOH

Answer 16

Fe(H2O)4(OH)2(s)
green ppt goes brown on standing in air (dirty green)

Question 17

Copper(II) neutral complex with NaOH

Answer 17

Cu(H2O)4(OH)2(s)
blue ppt

Question 17

Iron(III) neutral complex with NaOH

Answer 17

Fe(H2O)3(OH)3(s)
brown ppt
(ppt may look orange-brown)

Question 17

Aluminium(III) neutral complex with NaOH

Answer 17

Al(H2O)3(OH)3(s) white ppt

Question 18

amphoteric

Answer 18

metal hydroxides that can act as an acid or a base

Question 19

how can we reverse the metal hydroxide neutral complex

Answer 19

by adding H+ and the complex acts as a base

Question 20

example of amphoteric metal hydroxide

Answer 20

Al(H2O)3(OH)3

Question 21

so if OH- is added to Al(H2O)3(OH)3 what happens

Answer 21

it acts as an acid as it donates a proton to form water and it forms Al(H2O)2(OH)4 -

Question 23

so if H3O+ is added to Al(H2O)3(OH)3 what happens

Answer 23

it acts as a base and accepts a proton to start reforming the water ligands and if it does this three times it can reform original [Al(H2O)6]3+

Question 24

is ammonia a strong or weak base

Answer 24

it is a weak base

Question 25

ammonia and water reaction

Answer 25

NH3 + H2O -> NH4+ + OH-

Question 26

why does ammonia react to form metal hydroxides

Answer 26

because it forms OH- the same ones you would get from a base

Question 27

are the metal hydroxide colours the same with adding OH- and Ammonia

Answer 27

yes they both form the solid neutral complexes

Question 28

excess ammonia ?

Answer 28

some metal hydroxides show a partial ligand subsittution

Question 29

example of excess ammonia displacement is ?

Answer 29

Cu(H2O)4(OH)2(s). partial ligand substitiion happens 2 H20s are substituted and 2 OH are substituted for 4 NH3 forming [Cu(H2O)2(NH3)4]2+(aq) deep blue solution

Question 30

what does adding sodium carbonate to 2+ metal aqua ions do

Answer 30

it forms metal carbonate precipitates

Question 31

what happens in the reaction

Answer 31

all 6 ligands are replaced with just one carbonate. the metal carbonate is solid. this is a complete substitution

Question 32

what does adding sodium carbonate to 3+ metal aqua ions do

Answer 32

because the 3+ ions are more acidic the carbonates react with the lots of H3O+ in solution so there is no ligand substitution. this removes H3O+ so equilibrium shifts to the right again and so the same neutral complex if formed with carbon dioxide and water. so you will see bubbles of Co2 with these reactions

Question 33

metal ion test practicle and safety

Answer 33

1. add sample of unknown into three test tubes
   2.add drop by drop NaOH then excess
2. the add small amount of ammonia and excess
   4.the add sodium carbonate drop by drop
   (where gloves and goggles because there are acidic cause irritation, ammonia in fume cupboard )

Question 34

what dissolves in excess NaOH

Answer 34

Al(H2O)3(OH)3

Question 35

which dissolves in excess ammonia

Answer 35

Cu(H2O)4(OH)2(s) dissolves and forms dark blue colour

Question 36

why does fe2+ need to be fresh

Answer 36

by is oxidises very readily with air to form Fe3+

Question 37

[Fe(H2O)6]2+ Action of Na2CO3(aq)

Answer 37

FeCO3(s) green ppt

Question 38

Action of Na2CO3 with copper aqua ion (aq)

Answer 38

CuCO3(s) blue-green ppt

Question 39

[CuCl4]2- solution colour [CoCl4]2- blue solution

Answer 39

yellow/green solution

Question 40

[CoCl4]2-

Answer 40

blue solution

Answer 41

it forms the aqueous [Cu(H2O)6]2+ complex
and not the chloride [CuCl4]2- complex.