F325 Module 3: Transition Elements

Front 1

Define transition metal

Back 1

A d block element that forms an ion with an incomplete d sub shell

Front 2

Define d block element

Back 2

They are found between Group 2 and Group 3, where electrons are filling d orbitals. The d sub shell is the HIGHEST ENERGY sub shell

Front 3

Which two elements are not classed as transition metals

Back 3

Scandium as it forms only the Sn3+ ion where d orbitals are empty
Zinc as it forms only the Zn2+ ion where d orbitals are full

Front 4

Energy levels when filling orbitals

Back 4

4s sub shell has a lower energy than the 3d sub shell, so the 4s orbitals fills first.

Front 5

Which two elements have orbitals filled differently?

Back 5

Chromium - the 3d and 4s orbitals all contain one electron (Ar 4s1 3d5)
Copper - the 3d orbitals are filled with only one electron in 4s (Ar 4s1 3d10)
To reduce electron repulsion a between outer electrons and increase stability

Front 6

Properties of transition metals

Back 6

General metal properties (high bp and mp, high densities)
Form compounds with different oxidation states
Form coloured compounds
Catalyse reactions

Front 7

Colours of compounds

Back 7

Front 8

Transition metals as catalysts

Back 8

They provide a surface on which a reaction can take place, the reactants are adsorbed then desorbed
They provide a lower activation energy

Front 9

Important reactions catalysed by transition metals

Back 9

The Haber Process - Fe increases rate and lowers temp
The Contact Process - Vanadium oxide (+5) manufacture of H2SO4
Hydrogenation of Alkenes - nickel lowers temp and pressure

Front 10

Precipitation reactions with NaOH: Cu2+

Back 10

Cu2+ + 2OH- ---> Cu(OH)2
Pale blue solution - pale blue precipitate

Front 11

Co2+ and NaOH

Back 11

Co2+ + 2OH- ---> Co(OH)2
Pink solution - blue precipitate, turning beige in prescience of air

Front 12

Fe2+ and NaOH

Back 12

Fe2+ + OH- --> Fe(OH)2
Pale green solution - green precipitate, turning rusty brown on standing due to oxidation

Front 13

Fe3+ + NaOH

Back 13

Fe3+ + 3OH- ---> Fe(OH)3
Pale yellow solution ---> rusty brown precipitate

Front 14

Define complex ion

Back 14

A transition metal ion bonded to one or more ligands by coordinate bonds

Front 15

Define ligand

Back 15

A molecule or ion that can donate a pair of electrons with the transition metal ion to form a coordinate bond

Front 16

The coordination number

Back 16

The total number if coordinate bonds formed between a central metal ion and its ligands

Front 17

Common ligands

Back 17

They all have one or more lone pairs of electrons in their outer energy level
Water, :OH2 Ammonia, :NH3
Cyanide, :CN- Hydroxide :OH-

Front 18

Define monodentate ligand

Back 18

A ligand that donates just one pair of electrons to the central metal ion to form one coordinate bond

Front 19

The octahedral shape, picture and bond angle

Back 19

Six coordinate bonds, four of the ligands are in the same plane, one is above and one below
Bond angle is 90

Front 20

Define stereoisomers

Back 20

Species with the same structural formula but with a different arrangement of the atoms in space

Front 21

Name the two types of stereoisomers

Back 21

Cis-trans isomerism
Optical isomerism

Front 22

How can cis-trans occur and a diagram/ example

Back 22

When octahedral complexes contain four of one ligand and two of another e.g (Co(NH3)4(Cl2)+ forms a purple cis isomer an green trans

Front 23

Cis trans in four coordinate complexes

Back 23

They have a square planar shape, and must contain two of one ligand and two of another
E.g NiCl2(NH3)2

Front 24

Define bidentate ligand

Back 24

The ligand can donate two lone pairs of electrons to the central metal ion to form two coordinate bonds
They form octahedral complexes with coordinate number 6

Front 25

Can bidentate ligands show cis-trans isomerism?

Back 25

Yes, e.g (Cr(C2O4)2(H2O)2)-

Front 26

What are the requirements for optical isomerism?

Back 26

A complex with three molecules or ions of a bidentate ligand
A complex with two molecules or ions of a bidentate ligand and two molecules or ions of a monodentate ligand
A complex with one hexadenate ligand

Front 27

What are optical isomers

Back 27

Non superimposable mirror images of each other. One if the isomers rotates plane polarised light clockwise and the other anticlockwise

Front 28

Define ligand substitution

Back 28

A reaction in which one ligand in a complex ion is replaced by another ligand

Front 29

Define ligand substitution

Back 29

A reaction in which one ligand in a complex ion is replaced by another ligand

Front 30

Reaction of copper(II) ions and ammonia

Back 30

On addition of a small amount of ammonia a pale blue precipitate of Cu(OH)2 forms
On addition of excess ammonia a deep blue solution of (Cu(NH3)4(H2O)2)2+ forms
(Cu(H2O)6) + 4NH3 <---> (Cu(NH3)4(H2O)2)2+ + 4H2O

Front 31

Reaction of copper(II) ions and hydrochloric acid

Back 31

(Cu(H2O)6)2+ + 4Cl- <--> (CuCl4)2- + 6H2O
Pale blue solution - green solution - yellow (excess HCl)
(CuCl4)2- has four ligands as chloride ligands are larger than water ligands and have stronger repulsions, so fewer can fit round the Cu ion

Front 32

Reaction of cobalt(II) ions and con HCl

Back 32

(Co(H2O)6)2+ + 4Cl-<--> (CoCl4)2- + 6H2O
Pink solution - blue solution

Front 33

Reaction of copper(II) ions and hydrochloric acid

Back 33

(Cu(H2O)6)2+ + 4Cl- <--> (CuCl4)2- + 6H2O
Pale blue solution - green solution - yellow (excess HCl)
(CuCl4)2- has four ligands as chloride ligands are larger than water ligands and have stronger repulsions, so fewer can fit round the Cu ion

Front 34

Reaction of cobalt(II) ions and con HCl

Back 34

(Co(H2O)6)2+ + 4Cl-<--> (CoCl4)2- + 6H2O
Pink solution - blue solution

Front 35

Haemoglobin and ligand substitution

Back 35

Haemoglobin consists o four harm group, each harm group has an Fe2+ ion at its centre which oxygen can bind to.
This means red blood cells can either substitute or release oxygen

Front 36

Reaction of copper(II) ions and hydrochloric acid

Back 36

(Cu(H2O)6)2+ + 4Cl- <--> (CuCl4)2- + 6H2O
Pale blue solution - green solution - yellow (excess HCl)
(CuCl4)2- has four ligands as chloride ligands are larger than water ligands and have stronger repulsions, so fewer can fit round the Cu ion

Front 37

Reaction of cobalt(II) ions and con HCl

Back 37

(Co(H2O)6)2+ + 4Cl-<--> (CoCl4)2- + 6H2O
Pink solution - blue solution

Front 38

Haemoglobin and ligand substitution

Back 38

Haemoglobin consists o four harm group, each harm group has an Fe2+ ion at its centre which oxygen can bind to.
This means red blood cells can either substitute or release oxygen

Front 39

Why is less oxygen transported in presence of CO

Back 39

CO has a higher stability constant than oxygen and therefore CO forms stronger bonds with haemoglobin, so less room for oxygen to bob to harm group.

Front 40

Reaction of copper(II) ions and hydrochloric acid

Back 40

(Cu(H2O)6)2+ + 4Cl- <--> (CuCl4)2- + 6H2O
Pale blue solution - green solution - yellow (excess HCl)
(CuCl4)2- has four ligands as chloride ligands are larger than water ligands and have stronger repulsions, so fewer can fit round the Cu ion

Front 41

Reaction of cobalt(II) ions and con HCl

Back 41

(Co(H2O)6)2+ + 4Cl-<--> (CoCl4)2- + 6H2O
Pink solution - blue solution

Front 42

Haemoglobin and ligand substitution

Back 42

Haemoglobin consists o four harm group, each harm group has an Fe2+ ion at its centre which oxygen can bind to.
This means red blood cells can either substitute or release oxygen

Front 43

Why is less oxygen transported in presence of CO

Back 43

CO has a higher stability constant than oxygen and therefore CO forms stronger bonds with haemoglobin, so less room for oxygen to bob to harm group.

Front 44

Reaction of copper(II) ions and hydrochloric acid

Back 44

(Cu(H2O)6)2+ + 4Cl- <--> (CuCl4)2- + 6H2O
Pale blue solution - green solution - yellow (excess HCl)
(CuCl4)2- has four ligands as chloride ligands are larger than water ligands and have stronger repulsions, so fewer can fit round the Cu ion

Front 45

Reaction of cobalt(II) ions and con HCl

Back 45

(Co(H2O)6)2+ + 4Cl-<--> (CoCl4)2- + 6H2O
Pink solution - blue solution

Front 46

Haemoglobin and ligand substitution

Back 46

Haemoglobin consists o four harm group, each harm group has an Fe2+ ion at its centre which oxygen can bind to.
This means red blood cells can either substitute or release oxygen

Front 47

Why is less oxygen transported in presence of CO

Back 47

CO has a higher stability constant than oxygen and therefore CO forms stronger bonds with haemoglobin, so less room for oxygen to bob to harm group.

Front 48

Define the stability constant, Kstab

Back 48

The equilibrium constant for an equilibrium existing between a transition metal ion surrounded by water ligands and the complex ion formed when the same ion has undergone ligand substitution.

Front 49

Reaction of copper(II) ions and hydrochloric acid

Back 49

(Cu(H2O)6)2+ + 4Cl- <--> (CuCl4)2- + 6H2O
Pale blue solution - green solution - yellow (excess HCl)
(CuCl4)2- has four ligands as chloride ligands are larger than water ligands and have stronger repulsions, so fewer can fit round the Cu ion

Front 50

Reaction of cobalt(II) ions and con HCl

Back 50

(Co(H2O)6)2+ + 4Cl-<--> (CoCl4)2- + 6H2O
Pink solution - blue solution

Front 51

Haemoglobin and ligand substitution

Back 51

Haemoglobin consists o four harm group, each harm group has an Fe2+ ion at its centre which oxygen can bind to.
This means red blood cells can either substitute or release oxygen

Front 52

Why is less oxygen transported in presence of CO

Back 52

CO has a higher stability constant than oxygen and therefore CO forms stronger bonds with haemoglobin, so less room for oxygen to bob to harm group.

Front 53

Define the stability constant, Kstab

Back 53

The equilibrium constant for an equilibrium existing between a transition metal ion surrounded by water ligands and the complex ion formed when the same ion has undergone ligand substitution.

Front 54

Kstab equations

Back 54

Products/reactants but leave water out as a product, as it is in excess and its concentration is virtually constant

Front 55

Reaction of copper(II) ions and hydrochloric acid

Back 55

(Cu(H2O)6)2+ + 4Cl- <--> (CuCl4)2- + 6H2O
Pale blue solution - green solution - yellow (excess HCl)
(CuCl4)2- has four ligands as chloride ligands are larger than water ligands and have stronger repulsions, so fewer can fit round the Cu ion

Front 56

Reaction of cobalt(II) ions and con HCl

Back 56

(Co(H2O)6)2+ + 4Cl-<--> (CoCl4)2- + 6H2O
Pink solution - blue solution

Front 57

Haemoglobin and ligand substitution

Back 57

Haemoglobin consists o four harm group, each harm group has an Fe2+ ion at its centre which oxygen can bind to.
This means red blood cells can either substitute or release oxygen

Front 58

Why is less oxygen transported in presence of CO

Back 58

CO has a higher stability constant than oxygen and therefore CO forms stronger bonds with haemoglobin, so less room for oxygen to bob to harm group.

Front 59

Define the stability constant, Kstab

Back 59

The equilibrium constant for an equilibrium existing between a transition metal ion surrounded by water ligands and the complex ion formed when the same ion has undergone ligand substitution.

Front 60

Kstab equations

Back 60

Products/reactants but leave water out as a product, as it is in excess and its concentration is virtually constant

Front 61

The value of Kstab

Back 61

A large value indicates the position of equilibrium lies to the right, complex ions are more stable and the ion is easily formed

Front 62

Potassium manganate as an oxidising agent

Back 62

It uses Mn in its +7 oxidation state which is purple, and when it is reduced to Mn2+ it goes colourless

Front 63

Potassium manganate as an oxidising agent

Back 63

It uses Mn in its +7 oxidation state which is purple, and when it is reduced to Mn2+ it goes colourless

Front 64

Equation of MnO4- and Fe2+

Back 64

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

Front 65

Potassium manganate as an oxidising agent

Back 65

It uses Mn in its +7 oxidation state which is purple, and when it is reduced to Mn2+ it goes colourless

Front 66

Equation of MnO4- and Fe2+

Back 66

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

Front 67

Redox titrations can calculate....

Back 67

The concentration of a transition metal ion in unknown solution
The percentage composition of a metal in a solid sample/alloy

Front 68

Potassium manganate as an oxidising agent

Back 68

It uses Mn in its +7 oxidation state which is purple, and when it is reduced to Mn2+ it goes colourless

Front 69

Equation of MnO4- and Fe2+

Back 69

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

Front 70

Redox titrations can calculate....

Back 70

The concentration of a transition metal ion in unknown solution
The percentage composition of a metal in a solid sample/alloy

Front 71

Potassium manganate as an oxidising agent

Back 71

It uses Mn in its +7 oxidation state which is purple, and when it is reduced to Mn2+ it goes colourless

Front 72

Equation of MnO4- and Fe2+

Back 72

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

Front 73

Redox titrations can calculate....

Back 73

The concentration of a transition metal ion in unknown solution
The percentage composition of a metal in a solid sample/alloy

Front 74

Iodine and sodium thiosulfate

Back 74

2(S2O3)2- +I2 ---> 2I- + S4O62-