Transition Metals

Question 1

Transition metal

Answer 1

Element that forms at least one stable ion with a partially filled d subshell

Question 2

Heterogenous Catalyst

Answer 2

Catalyst that is in a different state from the reactants

Question 3

Transition Metal Ions as Catalysts

Answer 3

Act as homogenous catalysts (same state reactants)

Question 4

Transition Metals As Catalysts

Answer 4

Heterogenous Catalysts

Question 5

How do Heterogenous Catalysts Work

Answer 5

Chemisorption
Reactant molecules adsorbed onto catalyst surface - bonds weakened and molecules held in more favourable orientation for reaction
Products desorbed

Question 6

Iron in Haber Process

Answer 6

Question 7

Vanadium Oxide in Contact Process

Answer 7

Question 8

Nickel in Hydrogenation Reactions

Answer 8

Question 9

Pt/Rh in Catalytic Oxidation of Ammonia

Answer 9

Question 10

Physical Properties Transition Metals

Answer 10

•good conductors electricity - high densities

•ions in aqueous solution often coloured

•many from coloured complexes

•aqueous metal ions are actually hexaaqua cations
-Ni2+ = [Ni(H2O)6]2+(aq)

Question 11

Electronic Configurations Transition Metals

Answer 11

•3d fills after 4s

•Cr: [Ar] 3d5 4s1
•Cu: [Ar] 3d10 4s1

•First series of t-metal atoms lose their 4s electrons first when forming ions

Question 12

Complex

Answer 12

Central Metal atom or ion that is surrounded by ligands which are bonded to the central atom/ion by coordinate bonds

Question 13

Ligand

Answer 13

Anion or molecule with a lone pair of electrons that forms a coordinate bond with a central metal atom or ion in a complex

Question 14

How are Complexes written

Answer 14

Question 15

Neutral Ligands

Answer 15

aqua - H2O
ammine - NH3
1,2-diaminoethane(en) - H2NCH2CH2NH2

Question 16

Anion Ligands

Answer 16

Chloro - Cl-
Cyano - CN-
Thiocyano - SCN-
edta4-

Question 17

Monodentate Ligands

Answer 17

Ligands that use only one one pair of electrons to form one coord bond with the central metal atom/ion in a complex

Question 18

Bidentate Ligands

Answer 18

use two lone pairs of electrons to form two coord bonds with central atom/ion in a complex

Question 19

Polydentate Ligands

Answer 19

Ligands that use many lone pairs of electrons to form more than 2 coordinate bonds with the central metal atom/ion in a complex

Question 20

Hexadentate Ligands

Answer 20

use 6 lone pairs to form more than 2 coordinate bonds with central metal atom/ion in a complex

edta4-

Question 21

Water as A Ligand

Answer 21

Cannot act as bidentate despite 2 lone pairs

Lone pairs not far enough separated on ligand to form separate coordinate bonds

Question 22

Charge on Complex if Ligand Neutral

Answer 22

Same as oxidation state of metal atom/ion that is

Question 23

Charge in complex if ligand negatively charged

Answer 23

Oxidation State + (no. ligands x negative charge)

Question 24

Coordination Number

Answer 24

Number of coordinate bonds to a central metal atom/ion in a complex

[Ni(edta)]2- = 6 as hexadentate
[CuCl4]2- = 4

Question 25

Shape of Complex Coord 2

Answer 25

Linear 180° bond angle

Question 26

Shape of Complex Coord 4

Answer 26

Tetrahedral 109.5° bond angle

Question 27

Shape of Complex Coord 4 but different ligands

Answer 27

Square Planar 90° bond angle

Question 28

Shape of Complex Coord 6

Answer 28

Octahedral 90° bond angle

Question 29

Coordinate bonds on Drawing

Answer 29

Arrow with Head from ligand to Metal Atom

Question 30

Ligand Strength

Answer 30

•depends on availability lone pair •lone pairs more easily donated from less EN atoms •Moving down halide group - ions become weaker ligands (size of ions and strength of coord bond) •Alkyl groups in amines push e- towards N - destabilise lone pair - more likely to be donated

Question 31

Ligand Replacement

Answer 31

Stronger ligand replaces weaker ligands in a complex Can be explained in terms of entropy - more species (ligands) mire disordered Higher conc of weaker ligand can replace stronger ligand

Question 32

Order if strength ligands Decreasing Order

Answer 32

•CN- •H2NCH2CH2NH2 •NH3 •H2O •OH- •F- •Cl- •Br- •I-

Question 33

Reaction [Cr(H2O)6]3+ with NaOH and NH3

Answer 33

Green Solution NaOH: Green-Blue ppt NH3: Green-Blue ppt Excess NaOH: Green Solution Excess NH3: not soluble

Question 34

Mn2+ with NaOH and NH3

Answer 34

Pink solution NaOH/NH3: White ppt, darkens to black on standing Excess NaOH/NH3: Not soluble

Question 36

Fe2* with NaOH and NH3

Answer 36

Green Solution NaOH/NH3: Green ppt Excess: Not soluble

Question 37

Fe3+ with NaOH and NH3

Answer 37

orange solution NaOH/NH3: Brown ppt Excess: not soluble

Question 38

Co2+ with NaOH and NH3

Answer 38

Pink NaOH/NH3: blue ppt Excess NaOH: not soluble Excess NH3: Yellow solution changes to brown on standing

Question 39

Ni2+ with NaOH and NH3

Answer 39

Green Solution NaOH/NH3: green ppt Excess NaOH: not soluble Excess NH3: Blue solution

Question 40

Cu2+ with NaOH and NH3

Answer 40

Blue Solution NaOH/NH3: Blue ppt Excess NaOH: not soluble Excess NH3: Dark Blue Solution

Question 41

Chromium(III) Colour

Answer 41

Green Solution +3 OS

Question 42

Chromium(III) Hydroxide Colour

Answer 42

Green-Blue Solid +3 OS

Question 43

Hexahydroxochromate(III) Colour

Answer 43

Green Solution +3 OS

Question 44

Chromate(VI) Colour

Answer 44

Yellow Solution +6 OS

Question 45

Dichromate(VI) Colour

Answer 45

Orange Solution +6 os

Question 46

VO2 + name, colour, os

Answer 46

Dioxovandium(v) ion Yellow Solution +5

Question 47

VO2+

Answer 47

Oxovanadium(IV) ion Blue solution +4

Question 48

V3+

Answer 48

Vanadium(III) ion Green solution +3

Question 49

V2+

Answer 49

Vanadium(II) ion Violet solution +2

Question 50

How is +5 os achieved in Vanadium

Answer 50

Acidified Ammonium Vanadate(v) (NH4VO3)

Question 51

Vanadium Reduction +5 to +4

Answer 51

Question 52

Vanadium Reduction +4 to +3

Answer 52

Question 53

Vanadium Reduction +3 to +2

Answer 53