module 5 (p2)

Question 1

what are precipitation reactions

Answer 1

acid-base reactions

Question 2

what does the charge of the acid denote

Answer 2

the number of OH- ions needed to react

Question 3

what is the colour change when hexaquacopper (II) is reacted with NaOH or NH3

Answer 3

pale blue solution –> pale blue ppt

Question 4

what is the colour change when hexaquamanganese (II) reacts with NaOH or NH3

Answer 4

pale pink solution –> brown ppt.

Question 5

what is the colour change when hexaquairon (II) reacts with NaOH

Answer 5

pale green solution –> green ppt.

Question 6

what’s the colour change when hexaquairon (III) reacts with NaOH

Answer 6

pale yellow solution –> rusty brown ppt.

Question 7

what’s the colour change when hexaquachromium (III) reacts with NaOH

Answer 7

green solution –> green ppt.

Question 8

which compounds are soluble in excess

Answer 8

chromium

Question 9

what’s the ionic equation for Mn2+ reacting with NaOH

Answer 9

Mn2+ + 2OH- -> Mn(OH)2

Question 10

what’s the ionic equation for Fe3+ reacting with NaOH

Answer 10

Fe3+ + 3OH- -> Fe(OH)3

Question 11

what’s the equation for chromium in excess with NaOH

Answer 11

[Cr(OH)3(H2O)3] + 6OH -> [Cr(OH)6]3- + 3H2O + 3OH-

Question 12

give the reaction for the reaction of hexaquairon (III) with NH3

Answer 12

[Fe(H2O)6]3+ + 3NH3 -> [Fe(OH)3(H2O)3] + 3NH4+

Question 13

which complex ion is soluble in excess of NH3

what colour does the solution form

Answer 13

Cu2+

deep blue

Question 14

define a transition metal

Answer 14

d-block element which forms an incomplete ion

Question 15

what are the properties of TM

Answer 15

various oxidative states

form coloured compounds

act as catalysts

Question 16

define a coordinate bond

Answer 16

shared pair of electrons are donated to the TM

Question 17

define a ligand

Answer 17

molecule/ion that donates pair(s) of electrons to TM ion forming coordinate bond(s)

Question 18

what is the formula of the ethanoate ion

Answer 18

C2O4 2-

Question 19

what is the reaction of hexaquacopper (II) with dilute ammonia

Answer 19

[Cu(H2O)6]2+ + 2NH3 –> [Cu(OH)2(H2O)4] + 2NH4+

Question 20

what is the reaction of hexaquacopper (II) in concentrated (excess) ammonia

Answer 20

[Cu(OH)2(H2O)4] + 4NH3 –> [Cu(NH3)4(H2O)2]2+ + 2H2O + 2OH-

Question 21

what is the colour change in the reaction of hexaquacopper (II) in concentrated (excess) ammonia

Answer 21

pale blue ppt –> deep blue solution

Question 22

what is the reaction of hexaquachromium (III) in concentrated (excess) ammonia

Answer 22

[Cr(OH)3(H2O)3] + 6NH3 –> [Cr(NH3)6]3+ + 3H2O + 3OH-

Question 23

what is the colour change in the reaction of hexaquachromium (III) in concentrated (excess) ammonia

Answer 23

green ppt –> purple solution

Question 24

what does cis-trans isomerism only apply to what shape molecule in TM ions

Answer 24

square planar

Question 25

what is a cis square planar molecule have angles between the same groups

Answer 25

90 degrees

Question 26

what is a trans square planar molecule have angles between the same groups

Answer 26

180 degrees

Question 27

what is cisplatin

Answer 27

binds to DNA and prevents cell division anti cancer [PtCl2(NH3)2]

Question 28

what are the risks associated with cisplatin

Answer 28

prevents normal cells from respiring side effects (nausea, vomiting, etc.) can develop resistance to cisplatin

Question 29

what is the reaction of the oxidation of Fe2+ in manganate ion

Answer 29

5Fe2+ + MnO4- + 8H- --> Mn2+ + 5Fe3+ + 4H2O

Question 30

what are the colour changes in the oxidation of Fe2+

Answer 30

MnO4- is purple Mn2+ is colourless the endpoint for the reaction is a tinge of pink

Question 31

what is the reaction for the reduction of Fe3+

Answer 31

2Fe3+ + 2I- --> 2Fe2+ + I2

Question 32

what are the colour changes in the reduction of Fe3+

Answer 32

Fe3+ is rusty brown Fe2+ is green I2 is dark brown the colour change is overrided from rusty brown to dark brown (can't see green)

Question 33

what is the reaction for oxidation of Cr3+

Answer 33

2Cr3+ + 3H2O + 10OH- --> 2CrO4 2- + 8H2O

Question 34

what are the colour changes in the reaction for oxidation of Cr3+

Answer 34

Cr3+ is green CrO4 2- is yellow

Question 35

what is the reaction for the reduction of dichromate ion

Answer 35

Cr2O7 2- + 14H+ + 3Zn --> 2Cr3+ + 3Zn2+ + 7H2O

Question 36

what is the colour changes for the reduction of the dichromate ion

Answer 36

dichromate ion is orange chromium (III is green

Question 37

what is the ligand substitution reaction for hexaquacopper (II) in ammonia

Answer 37

[Cu(H2O)6]2+ + 4NH3 --> [Cu(NH3)4(H2O)2]2+ + 4H2O

Question 38

what is the colour change for the ligand substitution reaction for hexaquacopper (II) in ammonia

Answer 38

pale blue solution --> deep blue solution

Question 39

what is the ligand substitution reaction for hexaquacopper (III) in chloride ions

Answer 39

[Cu(H2O)6]2+ + 4Cl- --> [CuCl4]2- + 6H2O

Question 40

what is the colour change for the ligand substitution reaction for hexaquacopper (II) in chlorine

Answer 40

pale blue solution --> yellow solution

Question 41

what is the ligand substitution reaction for hexaquachromium (III) in ammonia

Answer 41

[Cr(H2O)6]3+ + 6NH3 --> [Cr(NH3)6]3+ + 6H2O

Question 42

what is the colour change for the ligand substitution reaction for hexaquachromium (III) in ammonia

Answer 42

violet solution --> purple solution

Question 43

why in the ligand substitution reaction for hexaquacopper (II) in chlorine does the complex change shape

Answer 43

chloride ions are larger than water molecules so only 4 fit around copper change of shape from octahedral (blue) to tetrahedral (green)