Transition metal chemistry

Question 1

Transition metals

Answer 1

• hard, high melting solids
• conduct heat and electricity
• readily lose electrons to form stable cations
• variety of oxidation states available to most
• form a wide range of coordination compounds with different ligands and molecular geometrics centre on metal ions
• many are highly coloured and/or paramagnetic

Question 2

Aufbau principle

Answer 2

electrons are added to the lowest energy orbital first

Question 3

Hund’s rule

Answer 3

electrons fill empty orbitals before pairing and the unpaired electrons adopt the same spin values

Question 4

Pauli exclusion principle

Answer 4

no two electrons may have the same set of quantum numbers (n, l, mI, ms)

Question 5

groups 3 to 7 redox

Answer 5

highest oxidation state corresponds to group number

Question 6

platinum metals - important in catalysis

Answer 6

• Ruthenium
• Osmium
• Iridium
• Palladium
• Platinum
• Rhodium
  Form stable cations in water

Question 7

d block ions

Answer 7

lost s electrons before d electrons
Mn2+ and Fe3+ are d5 ions

Question 8

lower oxidation states what compound type

Answer 8

ionic

Question 9

higher oxidation states what compound type

Answer 9

covalent

Question 10

f-block/group 3/elements of the first transition series (not Cu) react with aqueous solution of acids to give what?

Answer 10

hydrogen gas and solutions of corresponding salts

Question 11

Transition metals and halogens form?

Answer 11

anhydrous halides

Question 12

anhydrous halides reaction from halogen and metal

Answer 12

2Fe + 3Cl2 –> 2FeCl3 iron (III) chloride

Question 13

anhydrous halide reaction from metal halide and additional metal

Answer 13

Fe + 2FeCl3 –> 3FeCl2 iron (II) chloride
gives metal halide of lower oxidation state

Question 14

Ox state of product of F + transition metal

Answer 14

highest possible

Question 15

synthesis of aqueous sol of halides

Answer 15

react with salts of hydrohalic acids
NiCo3 + 2HF –> NiF2(aq) + H2O + CO2
nickel (II) fluoride
Co(OH)2 + 2HBr –> CoBr2(aq) + 2H2O
cobalt (II) bromide

Question 16

Transition metal + acid

Answer 16

dissolves to halide salt and hydrogen gas
Mn + 2HCl –> MnCl2 +H2

Question 17

Electronegativity and ox states

Answer 17

transition metals halides with low ox. states are more ionic

Question 18

heavy d-block elements have significant covalent character

Answer 18

.

Question 19

oxides and ox. state

Answer 19

low ox = ionic
high ox = covalent

Question 20

Oxides and ph

Answer 20

low ox = basic
high ox = acids

Question 21

Soluble hydroxide + aq sol of transition metal

Answer 21

gelatinous precipitate
sometimes the precipitate is a hydrated oxide (composed of metal ion, oxide ions and water of hydration)

Question 22

transition metal salt + soluble carbonate salt

Answer 22

insoluble carbonate

Question 23

carbonates + acids

Answer 23

metal salts, CO2 and H2O

Question 24

Carbonates decompose on heating to form

Answer 24

transition metal oxides

Question 25

coordinate covalent bond

Answer 25

donation of electrons from lewis base/ligand to lewis acid/central metal atom

Question 26

Coordination bonding

Answer 26

secondary valence secondary valence electrons don't have to be bound to a charged species

Question 27

Coordination compounds/werner complexes

Answer 27

ligands bond to a metal central atom

Question 28

lewis acid

Answer 28

metal

Question 29

lewis base

Answer 29

ligand

Question 30

Common neutral ligands

Answer 30

water, ammonia, pyridine

Question 31

common anionic ligands

Answer 31

cyanide, nitrate, carbonate, sulphate

Question 32

monodentate ligands

Answer 32

connect with the central atom through one ligand

Question 33

polydentate ligand

Answer 33

same ligand attaches multiple times at different points

Question 34

chelation

Answer 34

polydentate ligands attaching to central atom

Question 35

some bidentate ligands

Answer 35

ethylenediamine

Question 36

macrocylic ligands

Answer 36

polydentate ligands in a ring

Question 37

macrocycles in biological processes

Answer 37

used to immobilise metal ions and to increase their reactivity

Question 38

naming coordination complexes

Answer 38

if ionic, name cation then anion ligand first then central ligands alphabetically multiples of a ligand -> di/tri/tetra if cation/neutral metal name is same with ox state at the end if anion then add ate

Question 39

lanthanides

Answer 39

silvery metals abundant +3 oxidation states mainly

Question 40

actinides

Answer 40

radioactive +3 oxidation states mainly

Question 41

only actinides in nature

Answer 41

thorium and uranium

Question 42

condensed electron config of lanthanides

Answer 42

[noble gas] ns2 (n - 2)4fx (n - 1)d0 exceptions: Ce, Gd and Lu have 5d1

Question 43

crystal field theory

Answer 43

- Occurs for the d-orbitals of transition metals - The metal ion and the ligand electron pairs are treated as point charges - The interaction between them is purely electrostatic (ionic) - If the ligand is charged: ion-ion interaction; if ligand is neutral: ion-dipole interaction

Question 44

Porphyrins in biology

Answer 44

tetradentate macrocycle metalloporphyrin e.g. haeme b vital to life

Question 45

colours of d0 and d10 transition metals

Answer 45

white solids i.e. titanium (IV) oxide and copper (I) iodide

Question 46

how does colour arise in partially filled transition metals

Answer 46

transition of element from t2g to 3g by UV light

Question 47

relationship between value of delta-o and wavelength max

Answer 47

direct relationship for d1 metals in Ti (III), delta-o = wavelength max

Question 48

determining colour transmitted

Answer 48

opposite on colour wheel to whats absorbed

Question 49

Ti (III) colour transmitted

Answer 49

violet

Question 50

colour wheel nm

Answer 50

400, 430, 480, 560, 590, 630, 700

Question 51

spectrochemical series

Answer 51

list of ligands based on the strength of their interactions with metal ions

Question 52

strong field

Answer 52

high delta-o low spin shorter wavelength absorbed CN

Question 53

weak field

Answer 53

low delta-o high spin longer wavelength absorbed H2O F