Transition metals

Question 1

What type of bond is formed between water and copper in a TMI?

Answer 1

Co-ordinate bond

Question 2

How many water molecules surround copper in its TMI?

What is the name of the shape formed?

Answer 2

6

Octahedral

Question 3

What is a ligand?

Answer 3

A lone pair e- donor

Question 4

Name [Cu(H₂O)₆]²⁺

Answer 4

Hexaaquacopper II

Question 5

What is the relationship between charge density and acidity?

Answer 5

As charge density increases, acidity increases (pH decreases)

Question 6

Why does HCD increase acidity?

Answer 6

As charge density increases, FoA between cations and oxygen in water increases

Weakens O-H bond

H⁺ can be donated more easily

Question 7

What type of reaction is the acidification of a hexaaqua ion?

Answer 7

Hydrolysis

Question 8

What is the equation of the hydolysis of hexaaqua copper II?

Answer 8

[Cu(H₂O)₆]²⁺ + H₂O → [Cu(H₂O)₅(OH)]⁺ + H₂O

Question 9

Which direction does equilibrium shift if you add an acid to a hexaaqua ion?

Answer 9

Left

Question 10

Which direction does equilibrium shift if you add a base to a hexaaqua ion?

Answer 10

Right

Question 11

Why can bases such as ammonia and carbonate remove more protons than water?

How many protons can these bases remove?

Answer 11

They are stronger bases

Removes protons until charge is neutral and ppt forms

Question 12

Whichbase can remove all protons from a hexaaqua ion even after a ppt forms?

Answer 12

OH^-

Question 13

What is a transition metal?

Answer 13

D-block element forming 1 or more stable ions with a partially filled D-shell

Question 14

Do transition metals have a higher or lower bpt than S-block metals?

Answer 14

Higher

Question 15

Name a linear transition metal ion?

Answer 15

Tollen’s reagent

[Ag(NH₃)₂]⁺

Question 16

Name a square planar TMI

Answer 16

(cis/trans) platin

[Pt(Cl)(NH₃)]

Question 17

Name a tetrahedral TMI

Answer 17

[Cu(Cl)₄]^2-

Question 18

What is cis-platin used for and why is it more effective than transplatin?

Answer 18

Cancer drug

Stereospecificity means it is easier for Cl^- to bind to DNA

Question 19

What is the structure of cisplatin?

Answer 19

Question 20

What is the structure of transplatin?

Answer 20

Question 21

What is the structure of EDTA

Answer 21

Question 22

What is the charge ofo EDTA?

Answer 22

4-

Question 23

What is the equation for the reaction of [Cu(H₂O)₆]²⁺ with EDTA

Answer 23

[Cu(H₂O)₆]²⁺ + EDTA^4- → [Cu(EDTA)]^2- + 6H₂O

Question 24

What is the structure of oxylate?

Answer 24

Question 25

What type of ligand is oxylate?

Answer 25

Bidentate

Question 26

What is the equation for the reaction of [Cu(H₂O)₆]²⁺ with 1 molecule of oxylate?

Answer 26

[Cu(H₂O)₆]²⁺ + C₂O₄^2- → [Cu(C₂O₄)(H₂O)₄] + 2H₂O

Question 27

Describe the appearance of [Cu(C₂O₄)(H₂O)₄]

Answer 27

light blue ppt

Question 28

What is the planck equation?

Answer 28

E = hf Enery required to move e- to excited state is proportional to the frequency of the light _absorbed_

Question 29

Write equations for the 2 steps involved in the contact process using a vanadium(V) oxide catalyst Give the overall equation

Answer 29

V₂O_{5 (s)} + SO₂ → V₂O₄ + SO₃ V₂O₄ + ¹/₂O₂ → V₂O₅ Overall equation: SO₂ + ¹/₂O₂ → SO₃

Question 30

Write equations for the 2 steps involved in the reaction of iodide and peroxodisulfate with an iron catalyst Give the overall equation

Answer 30

S₂O₈^2- + 2Fe²⁺ → 2SO₄^2- + 2Fe³⁺ 2Fe³⁺ + 2I^- → 2Fe²⁺ + I₂ Overall equation: S₂O₈^2- + 2I^- → 2SO₄^2- + I₂

Question 31

Why is the reaction between iodide and peroxodisulfate very slow without a catalyst

Answer 31

Both are negative ions and so repel each other

Question 32

Name S₂O₈^2-

Answer 32

Peroxodislufate

Question 33

What catalyst is used in the reaction between I^- and S₂O₈^2- What type of catalysis is this?

Answer 33

Fe²⁺ Homogenous catalysis (all reactants and products are aqueous)

Question 34

What is the catalyst used in the contact process? What type of catalysis is this?

Answer 34

Vanadium (V) oxide V₂O₅ Heterogenous catalysis

Question 35

What is autocatalysis?

Answer 35

The catalyst of the reaction is a reaction product

Question 36

How does the rate of an autocatalysed reaction change with time?

Answer 36

Initial rate of reaction very slow then speeds up

Question 37

Write the 2 steps involved in the reaction of maganate and ethanedioate with an Mn²⁺ catalyst Give the overall equation

Answer 37

MnO₄^- + 8H⁺ + 4Mn²⁺ → 5Mn³⁺ + 4H₂O 2Mn³⁺ + C₂O₄^2- → 2Mn²⁺ + 2CO₂ Overall: MnO₄^- + 5C₂O₄^2- + 16H⁺ → 2Mn²⁺ + 5CO_{2 +} 8H₂O

Question 38

What is the catalyst in the reaction between manganate(VII) and ethanedioate? What type of catalysis is this?

Answer 38

Mn²⁺ Autocatalysis

Question 39

What colour is manganate (VII)?

Answer 39

Purple

Question 40

How does poisoning reduce the effectivness of a heterogenous catalyst?

Answer 40

Attaches to surface, therefore reducing the surface area

Question 41

How can poisonning be minimised in heterogenous catalysis?

Answer 41

Purify reactants

Question 42

What property of transition metals allows them to act as catalysts?

Answer 42

Variable oxidation states

Question 43

State and explain one risk associated with using cisplatin as an anti-cancer drug

Answer 43

May kill healthy cells by attaching to their DNA

Question 44

State the product formed when [Co(NH₃)₆]²⁺ reacts with H₂O₂ Describe the appearance of this complex What is the role of H₂O₂ in this reaction?

Answer 44

[Co(NH₃)₆]³⁺ Dark brown solution Oxidising agent

Question 45

What is the formula of the product when [Co(NH₃)₆]²⁺ reacts with excess H₂N(CH₂)₂NH₂ Explain why this compund is very stable

Answer 45

[Co(H₂NCH₂CH₂NH₂)₃]²⁺ Entropy change is positive

Question 46

What is the term for a substance that can act as both an acid and a base?

Answer 46

Amphoteric

Question 47

Write equations for the reaction between: * Aluminium oxide and hydrochloric acid * Aluminium oxide and sodium hydroxide

Answer 47

Al₂O₃ + 6HCl → 2AlCl₃ + 3H₂O Al₂O₃ + 2NaOH → 3H₂O + 2NaAl(OH)₄

Question 48

Define homogenous

Answer 48

Same phase/state

Question 49

Define complex ion

Answer 49

Has ligands linked by co-ordinate bonds

Question 50

In terms of electrons, explain why an aqueous solution of cobalt(II) sulfate has a red colour

Answer 50

Blue light is absorbed (from incident white light) Due to electrons moving to higher levels / electrons excited Red light that remains is reflected

Question 51

Write an equation to show how copper metal can be extracted from a dilute aqueous solution containing copper(II) ions using scrap iron Give the intial and final colour

Answer 51

Cu²⁺(aq) + Fe(s) → Cu(s) + Fe²⁺(aq) Initial: blue Final: green

Question 52

What property of transition metals makes them coloured?

Answer 52

Partially filled D-shell

Question 53

Define multidentate

Answer 53

Forms two or more co-ordinate bonds

Question 55

Explain why [Cu(H₂O)₆]²⁺ is blue

Answer 55

Absorbs certain frequencies of light d electrons excited Blue light transmitted

Question 56

Ionic equation for the reaction of dichromate ions with iron (II)

Answer 56

Cr₂O₇^2- + 6Fe²⁺ + 14H⁺ → 2Cr³⁺ + 7H₂O + 6Fe³⁺

Question 57

Ionic equation for Chromium and iron

Answer 57

C₂O₇^2- + 14H⁺ + 6Fe²⁺ → 2Cr³⁺ + 7H₂O + 6Fe³⁺

Question 58

Half equation for reduction of manganate

Answer 58

MnO₄^- + 8H⁺ + 5e^- → Mn²⁺ + 4H₂O