Transition metals

Question 1

state definition for transition metal

Answer 1

d-block element that can form at least one stable ion w/ an incomplete d sub-shell

Question 2

what is significant about Cr electron configuration ?

Answer 2

each 3d orbital has one electron - 4s orbital only contains one electron - more stability

Question 3

what is significant about Cu electron configuration ?

Answer 3

each 3d orbital has two electrons - 4s only has one electron - more stability

Question 4

which electrons are removed first for transition elements ions are formed ?

Answer 4

the 4s electrons

Question 5

what catalyses Zn + acid ?

Answer 5

Copper sulfate

Question 6

what catalyses decomposition of hydrogen peroxide ?

Answer 6

Manganate dioxide

Question 7

why are transition metals good catalysts ?

Answer 7

1. can transfer electrons to speed reactions

2. good at adsorbing substances to their surface to lower Ea

Question 8

transition metal ion + OH- —>

Answer 8

coloured metal hydroxide + water

Question 9

transition metal ion + ammonia —>

Answer 9

coloured metal hydroxide + ammonium

Question 10

state the colour change of Copper (||) ion to metal hydroxide

Answer 10

pale blue sol – blue ppt

Question 11

state the colour change of Iron (||) ion to metal hydroxide

Answer 11

pale green sol – green ppt (darkens)

Question 12

state the colour change of Iron (|||) ion to metal hydroxide

Answer 12

yellow sol – orange ppt (darkens)

Question 13

state the colour change of Manganese (||) ion to metal hydroxide

Answer 13

pale pink sol – pink ppt (darkens)

Question 14

state the colour change of Chromium (|||) ion to metal hydroxide

Answer 14

green sol – grey green ppt

Question 15

define complex ion

Answer 15

metal ion surrounded by coordinately bonded ligands

Question 16

what is a coordinate bond ?

Answer 16

(dative covalent) bonding electrons come from same atom

Question 17

what is a ligand ?

Answer 17

species which donates pair of electrons to central metal ion

Question 18

what is the coordinate number ?

Answer 18

no. of coordinate bonds

Question 19

what is a mono/bidentate ?

Answer 19

one lone pair / two lone pairs available for bonding

Question 20

what is cis-platin ?

Answer 20

complex of platinum (||) w/ two chloride ions and two ammonia molecules
(anti-cancer drug)

Question 21

how does cis-platin act to fight cancer ?

Answer 21

• chloride ligands easily displaced
• nitrogen atoms from DNA of cancerous cell displaces chloride ions
• cancerous cell now cannot reproduce by division and die

Question 22

what is bad about cis-platin ?

Answer 22

• also prevents normal cells from reproducing

- causes kidney damage

Question 23

give 3 examples of small ligands and state how many coordinate bonds form

Answer 23

water, CN-, ammonia

6

Question 24

give an example of a big ligand and how many coordinate bonds form

Answer 24

Cl-

4

Question 25

For ligand substitution of similar sized ligands ...

Answer 25

same no. of coordinate bonds and shape | charge may change

Question 26

For ligand substitution of different sized ligands ...

Answer 26

change in no. of coordinate bonds and shape | charge may change

Question 27

describe the structure of the complex ion of haemoglobin

Answer 27

Iron (||) w/ 6 coordinate bonds : - 4 Nitrogen - 1 Nitrogen from the the protein globin - 1 water

Question 28

describe the structure of the complex ion of oxyhaemoglobin

Answer 28

Iron (||) w/ 6 coordinate bonds : - 4 Nitrogen - 1 Nitrogen from the the protein globin - 1 oxygen

Question 29

how does carbon monoxide affect haemoglobin ?

Answer 29

- water substituted for CO ligand - carboxyhaemoglobin forms - strong bond formed

Question 30

what is the test for identifying transition elements ?

Answer 30

- add NaOH | - observe and identify w/ colour

Question 31

state colour of Ti (|||) ions & Ti (||) ions

Answer 31

||| purple | || violet

Question 32

state the colour change from VO2 + . VO 2+ . V 3+ . V 2+

Answer 32

VO2 + yellow VO 2+ blue V 3+ green V 2+ violet

Question 33

state colour of dichromate ions

Answer 33

orange

Question 34

state colour of Cr (|||) ions

Answer 34

green (violet)

Question 35

state colour of MnO4 - ions

Answer 35

purple

Question 36

state colour of MnO4 2- ions

Answer 36

green

Question 37

state colour of Mn 2+ ions

Answer 37

pale pink

Question 38

state colour of Iron (|||) ions

Answer 38

yellow

Question 39

state colour of Iron (||) ions

Answer 39

pale green

Question 40

state colour of Cobalt (||) ions

Answer 40

pink

Question 41

state colour of Nickel (||) ions

Answer 41

green

Question 42

state colour of Copper (||) ions

Answer 42

pale blue

Question 43

which metal ions darken w/ OH ?

Answer 43

Fe 2+ / 3+ and Mn 2+

Question 44

describe reaction of Cr3+ (aq) with 6NH3

Answer 44

- reversible ligand substitution - forms Cr(NH3)6 and water - violet to purple

Question 45

state colour change of chlorine substitution of Cu2+ (aq)

Answer 45

pale blue to yellow

Question 46

what occurs w/ Cu2+ (aq) with excess ammonia ?

Answer 46

Cu(NH3)4 (aq) forms | pale blue to deep blue

Question 47

Color and reagent of Fe2+ to Fe3+

Answer 47

acidified potassium manganate (|) | green to yellow

Question 48

Color and reagent of Fe3+ to Fe2+

Answer 48

Iodine ions | yellow to green

Question 49

Color and reagent of Cu2+ to Cu+

Answer 49

Iodine ions to for CuI | pale blue to off white ppt

Question 50

Color and reagent of CrO7 2- to Cr3+

Answer 50

orange to green | acidic and zinc