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A level Chemistry AQA Lewis > 3.2.5 - Transition Metals > Flashcards

3.2.5 - Transition Metals Flashcards

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1
Q

Which block are transition metals found in?

A

d-block

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2
Q

What is a transition metal?

A

A metal that can form one or more stable ions with a partially filled d sub-level

(d-orbital can contain up to 10 electrons)

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3
Q

State which period 4 d-block elements are transition metals

A

All period 4 d-block elements are transition metals expect scandium and zinc

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4
Q

What causes transition metals to have special chemical properties?

A

Incomplete d sub-level

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5
Q

Explain why scandium isn’t a transition metal

A
  • Scandium only forms one ion, Sc3+, which has empty d sub-level
    • Sc = [Ar] 3d1 4s2
    • When loses 3 electrons to form Sc3+
    • Ends up with electron configuration [Ar]
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6
Q

Explain why zinc isn’t a transition metal

A
  • Zinc only forms one ion, Zn2+, which has full d sub-level
    • Zn = [Ar] 3d10 4s2
    • Forms Zn2+ = loses 2 electrons both from 4s sub-level
    • ∴ keeps full 3d sub-level
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7
Q

Transition metals form ______ ions

A

positive

s electrons removed first & then d electrons

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8
Q
A
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9
Q

Name 4 special chemical properties of transition metals

A
  • Form complex ions
  • Form coloured ions
  • Good catalysts
  • Exists in variable oxidation states
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10
Q

Why do elements show variable oxidation states?

A
  • ∵ energy levels of 4s and 3d sub-levels are very close to one another
  • ∴ different no. of electrons can be gained or lost using fairly similar amounts of energy
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11
Q

Oxidation state +7

State colour of MnO4-

A

Purple

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12
Q

Oxidation state +6

State colour of Cr2O72-

A

orange

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13
Q

Oxidation state +5

State colour of VO2+

A

yellow

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14
Q

Oxidation state +4

State colour of VO2+

A

blue

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15
Q

Oxidation state +3

State colour of V3+

A

green

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16
Q

Oxidation state +3

State colour of Cr3+

A

violet/green

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17
Q

Oxidation state +3

State colour of Fe3+

A

purple/yellow

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18
Q

Oxidation state +2

State colour of V2+

A

Violet

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19
Q

Oxidation state +2

State colour of Mn2+

A

Pale pink

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20
Q

Oxidation state +2

State colour of Fe2+

A

Pale green

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21
Q

Oxidation state +2

State colour of Co2+

A

Pink

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22
Q

Oxidation state +2

State colour of Ni2+

A

green

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23
Q

Oxidation state +2

State colour of Cu2+

A

blue

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24
Q

Define a complex

A

A complex is a central metal atom or ion surrounded by co-ordinately bonded ligands

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25
Q

Define a co-ordinate bond

A

Covalent bond in which both electrons in the shared part come from the same atom

(In complex, they come from ligand)

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26
Q

Define a ligand

A

Atom, ion or molecule that donates a pair of electrons to a central transition metal ion to form a co-ordinate bond

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27
Q

Define co-ordination number

A

no. of co-ordinate bonds that are formed with the central metal ion

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28
Q

Name 2 examples of small ligands

A

H2O or NH3

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29
Q

If ligands are small (like H2O or NH3), state how many co ordinate bonds can fit around the central metal ion

A

6

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30
Q

Name an example of a bigger ligand

A

Cl-

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31
Q

If ligands are large (like Cl-), state how many co ordinate bonds can fit around the central metal ion

A

4

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32
Q

6 co-ordinate bonds mean an _____ shape

A

6 co-ordinate bonds mean an octahedral shape

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33
Q

State the bond angles for an octahedral shape

A

90°

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34
Q

Draw [Fe(H2O)6]2+ (aq)

A
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35
Q

State the formula of

A

[Co(NH3)6]3+ (aq)

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36
Q

Draw [Cu(NH3)4(H2O)2]2+ (aq)

A
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37
Q

4 co-ordinate bonds usually mean a ________ shape

A

4 co-ordinate bonds usually mean a tetrahedral shape

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38
Q

State the bond angles for a tetrahedral shape

A

109.5°

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39
Q

Draw [CuCl4]2-

A
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40
Q

4 co-ordinate bonds can form a ____ _____ shape

A

4 co-ordinate bonds can form a square planar shape

e.g. cisplatin

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41
Q

State the bond angles for a square planar shape

A

90°

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42
Q

Some silver complexes have 2 co-ordinate bonds and form a ______ shape

A

Some silver complexes have 2 co-ordinate bonds and form a linear shape

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43
Q

Draw [Ag(NH3)2]+ (Tollens’ reagent)

A
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44
Q

State the bond angles for a linear shape

A

180°

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45
Q

Overall charge on complex ion is its ___ ____ ____

A

total oxidation state

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46
Q

State how you would work out the oxidation state of a metal ion

A
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47
Q

Give the oxidation state of the cobalt ion in [CoCl4]2-

A
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48
Q

Give the oxidation state of the chromium ion in [CrCl2(H2O)4]+

A
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49
Q

Why must a ligand have at least one lone pair of electrons?

A

∵ otherwise it won’t have anything to use to form a co-ordinate bond

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50
Q

What are monodentates?

A

Ligands that only form 1 co-ordinate bond

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51
Q

What are multidentates?

A

Ligands that form more than 1 co-ordinate bond

e.g. EDTA4- has 6 lone pairs

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52
Q

What are bidentates?

A
  • (multidentate) ligands that can form 2 co-ordinate bonds
  • Donates an electron pair from two different atoms
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53
Q

Draw a ethane-1,2-diamine (en) molecule

A
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54
Q

Draw an ethanedioate (C2O42-) molecule

A
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55
Q

Name a multidentate ligand that forms 6 co-ordinate bonds with a metal ion

A
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56
Q

Describe the overall structure of haemoglobin

A

Haemoglobin contains Fe2+ ions, which are hexa-coordinated (6 co-ordinate bonds) = octahedral structure

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57
Q

Describe the haem part in haemoglobin

A
  • Haem is an iron(II) complex with a multidentate ligand
    • 4 co-ordinate bonds come from single multidenate ligand
    • 4 nitrogen atoms from same molecule co-ordinate around Fe2+ to form circle
    • This part of molecule is called haem
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58
Q

State where the other 2 co-ordinate bonds come from in haemoglobin (i.e. not N)

A

Other 2 co-ordinate bonds come from protein called globin, and oxygen or water molecule

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59
Q

What does the complex in haemoglobin allow it do?

A

Complex can transport oxygen to where its needed & then swap it for a water molecule

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60
Q

Explain how haemoglobin can transport oxygen to where its needed & then swap it for a water molecule

A
  1. In lungs (O₂ = high), O₂ substitutes water ligand and bonds co-ordinately to Fe(II) ion to form oxyhaemoglobin which is carried around the body in the blood
  2. When oxyhaemoglobin gets to place where O₂ is needed, oxygen molecule is exchanged for water molecule
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61
Q

Draw Haemoglobin

(with either water or oxygen)

A
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62
Q

Explain what happens to haemoglobin if CO is inhaled

A
  1. Haemoglobin swaps its water ligand for a CO ligand forming carboxyhaemoglobin
  2. CO = strong ligand & doesn’t readily exchange with oxygen or water ligands ∴ haemoglobin can’t transport oxygen
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63
Q

Complex ions can show _____ isomerism

A

optical isomerism (type of stereoisomerism)

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64
Q

What is optical isomerism?

A

Where ion can exist in 2 forms that are non-superimposable mirror images

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65
Q

When do complex ions show optical isomerism?

A

Happens with octahedral complexes when 3 bidentate ligands (e.g. ethane-1,2-diamine) co-ordinately bond with central metal ion (e.g. nickel)

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66
Q

Cis-Trans Isomers can form in _______ and ______ _____ Complexes

A

Cis-Trans Isomers can form in Octahedral and Square Planar Complexes

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67
Q

Describe octahedral complexes that show cis-trans isomerism

A

Octahedral complexes with 4 monodentate ligands of 1 type & 2 monodentate ligands of another type

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68
Q

Octahedral Complexes

When does a trans isomer occur?

A

If 2 odd ligands are opposite each other

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69
Q

Octahedral Complexes

When does a cis isomer occur?

A

If 2 odd ligands are next to each other

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70
Q

Describe square planar complexes that show cis-trans isomerism

A

Square planar complex ions that have 2 pairs of ligands

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71
Q

Square Planar Complexes

When does a trans isomer occur?

A
72
Q

Square Planar Complexes

When does a cis isomer occur?

A
73
Q

What happens to the 3d orbitals when ligands bond to ions?

A

Some of the orbitals gain energy which splits the 3d orbitals into 2 different energy levels

74
Q

Electrons tend to occupy the _____ ____

A

lower orbitals/ground state

75
Q

What do electrons need to jump to the higher orbitals (excited states) and where do they get this from?

A
  • They need energy equal to the energy gap, ΔE
  • Get this energy from visible light
76
Q

State the formula used to calculate the energy absorbed when electrons jump from the ground state to an excited state (i.e. ΔE)

A
77
Q

What affects the size of the energy gap (ΔE)?

A
  • Central metal ion
  • Its oxidation state
  • Ligands
  • Co-ordination number
78
Q

The larger the energy gap, the _____ the frequency of light that is absorbed

A

The larger the energy gap, the higher the frequency of light that is absorbed

79
Q

Explain why the colours of transition metal ions are complement of those that are absorbed

A
  1. When visible light hits transition metal ion, some frequencies are absorbed when d electrons jump to higher orbitals/are excited
    • Frequencies absorbed depend on size of energy gap (ΔE)
  2. Rest of frequencies transmitted or reflected
  3. These frequencies combine to make complementary colour of the absorbed frequencies = colour you see
  4. e.g. hydrated [Cu(H2O)6]2+ ions
    1. Absorb “red” light
    2. Rest of frequencies combine to produce complementary colour = blue
80
Q

Explain why some compounds appear white/colourless

A
  • If no 3d electron or 3d sub-level is full
  • = no electron will jump ∴ no energy absorbed
  • ∴ compound = white/colourless
81
Q

How can the colour of a complex be altered?

A

By any factors that can affect the size of the energy gap (ΔE)

82
Q

What is spectroscopy used to find?

A

The conc. of a solution by measuring how much light it absorbs

83
Q

Describe how you can use spectroscopy to find concentrations of transition metal ions

A
  1. White light shone through filter, that only lets through the colour of light that’s absorbed by the sample
  2. Light passes through sample to colorimeter
    • Calculates how much light was absorbed by the sample
  3. More conc. coloured solution is = more light it’ll absorb
84
Q

Describe how you can use light absorption measurement to find conc. of solution of transition metal ions

A
  • Produce a calibration curve
    • Involves measuring absorbance of known conc. of solutions & plotting results on a graph
  • Then can measure absorbance of your sample & read its conc. off the graph
85
Q

Ligand Substitution

If ligands are of similar size and the same charge, then the ________ and _____ of the complex ion doesn’t change

A

If ligands are of similar size and the same charge, then the co-ordination number and shape of the complex ion doesn’t change

86
Q

Ligand Substitution

If ligands are ______ ____, they’ll be a change in co-ordination number and shape

A

If ligands are different sizes, they’ll be a change in co ordination number and shape

87
Q

Ligand substitution reactions can be easily reversed. State when they can’t be.

A

When new complex ion is more stable than old one

88
Q

Give 2 examples of when ligand substitution reactions can’t be easily reversed

A
  • If new ligands form stronger bonds with central metal ion than old ligands did
  • Multidentate ligands form more stable complexes than monodentate ligands
89
Q

Explain why enthaply change for a ligand substitution reaction is usually very small

A

When ligand exchange reaction occurs, strength of co-ordinate bonds broken is often very similar to strength of new co-ordinate bonds being made

90
Q

Why is this reaction considered irreversible when it is actually reversible?

A
  • Equilibrium lies so far to the right
  • [Ni(NH2CH2CH2NH2)3]2+ is much more stable than [Ni(NH3)6]2+
    • ​Not accounted for by an enthalpy change
91
Q

What explains why multidentate ligands always form much more stable complexes than monodenate ligands?

A

The chelate effect

92
Q

Explain what the chelate effect is

A
  • When monodentate ligands are substitued with bidentate/multidentate ligands, the no. of particles in solution ↑
  • More particles = greater entropy
  • Reactions that result in greater entropy are more likely to occur

Difficult to reverse these reactions ∵ reversing = decrease in entropy

93
Q

Transition metals can exists in ___ ______ _____

A

variable oxidation states

94
Q

Describe how vanadium(V) ions can be reduced

A

By adding them to zinc metal in an acidic solution

95
Q

Write the equation for when VO2+(aq) reacts with Zn(s)

A
96
Q

Write the equation for when VO2+(aq) reacts with Zn(s)

A
97
Q

Write the equation for when V3+(aq) reacts with Zn(s)

A
98
Q

What does the redox potential of ion/atom tell you?

A

How easily the ion/atom is reduced to lower oxidation state

(same as electrode potentials)

99
Q

Larger redox potential, less _____ ion will be & more likely
it’s to be ______

A

Larger redox potential, less stable ion will be & more likely it’s to be reduced

100
Q

Redox potential of an ion _____ always be same as its standard electrode potential

A

WON’T

101
Q

What is the redox potential for a transition metal ion, when it changes from a higher to a lower oxidation state, influenced by?

A
  • pH
  • ligand
102
Q

Explain how different ligands affect redox potentials (& make them differ from standard electrode potentials)

A
  • Standard electrode potentials are measured in aqueous solution = aqueous ions will be surrounded by water ligands
  • Different ligands may make redox potential larger or smaller depending on how well they bind to a metal ion in particular oxidation state
103
Q

Explain how different pHs affect redox potentials

A
  • Some ions need H+ to be present in order to be reduced
  • Others release OH- ions into solution when they are reduced
  • pH of solution affects size of redox potential for these reactions
  • Redox potentials will be large in more acidic solutions, making ion more easily reduced
104
Q

What reaction does Tollens’ reagent use to distinguish between aldehydes and ketones? State the equation

A
105
Q

Describe how Tollens’ reagent is prepared

A

Add ammonia solution to silver nitrate solution to form colourless solution containing complex ion [Ag(NH3)2]+

106
Q

Describe what happens when aldehyde is added to Tollens’ reagent

A
  • Tollens’ reagent reacts to give silver mirror on inside of test tube
  • Aldehyde is oxidised to carboxylic acid, Ag+ ions are reduced to silver metal
107
Q

Write the equation for when Tollen’s reagent reacts with an aldehyde (RCHO)

A
108
Q

Titrations using Transition Element Ions are _____ Titrations

A

Redox

109
Q

Titrations with Transition Metals

What can you use the titrations to find out?

A

How much oxidising agent is needed to exactly react with a quantity of reducing agent

110
Q

Titrations with Transition Metals

Suggest an oxidising agent you can use

A

aqueous potassium manganate(VII)

111
Q

Titrations with Transition Metals

Suggest why aqueous potassium manganate(VII) is used as an oxidising agent

A
  • Contains purple manganate(VII) ions
  • Strong acidic conditions are needed for manganate(VII) ions to be reduced
112
Q

Titrations with Transition Metals

Suggest 2 reducing agents you can use

A
  • aqueous Fe2+ ions
  • aqueous C2O42- ion
113
Q

Titrations with Transition Metals

Describe a method

A
  1. Measure quantity of reducing agent using a pipette & add to conical flask
  2. Using a measuring cylinder, add 20 cm3 of dilute sulfuric acid to flask
    • This is in excess
  3. Add oxidising agent to reducing agent using burette
    • Swirling conical flask
  4. Oxidising agent added reacts with reducing agent
    • Reaction continues until all reducing agent is used up
    • Next drop added = mixture becomes colour of oxidising agent
  5. Stop when mixture in flask becomes tainted with colour of oxidising agent (end point) and record volume of oxidising agent added
    • Rough titration
  6. Do some accurate titrations
    • Do a few until you get 2 or more reading are within 0.10 cm3 of each other
114
Q
A
115
Q
A
116
Q

Why do transition metals and their compounds make good
catalysts?

A
  • ∵ change oxidation states by gaining or losing electrons within d orbitals
  • ∴ can transfer electrons to speed up reactions
117
Q

What is the catalyst used in the Contact Process to make sulfuric acid?

A

Vanadium(V) oxide

118
Q

Why is vanadium(V) oxide used as a catalyst in the Contact Process?

A
  • ∵ it’s able to oxidise SO2 to SO3 and it can be reduced to vanadium(IV) oxide
  • & then it’s oxidised back to vanadium(V) oxide by oxygen to react all over again
119
Q

Describe and state the 1st equation that occurs in the Contact Process. Include state symbols.

A
120
Q

Describe and state the 2nd equation that occurs in the Contact Process. Include state symbols.

A
121
Q

What are heterogenous catalyst?

A

A catalyst that’s in a different phase from the reactants

i.e. in a different physical state

122
Q

Where do reactions occur on in heterogenous catalysts?

A

Occur on on active sites on surface of heterogenous catalyst

123
Q

Explain why increasing SA of a catalyst increases the rate of a reaction

A

Increases no. of molecules that can react at same time

124
Q

What are often used to make the area of catalyst as large as possible?

A

Support mediums

125
Q

Explain how support mediums help to minimise the cost of a reaction?

A

∵ only small coating of catalyst is needed to provide large SA

126
Q

Name 2 heterogeneous catalysts

A
  • Iron in Haber Process (for making ammonia)
  • Vanadium(V) oxide in Contact Process
127
Q

State the overall equation for the Haber Process. Include the catalyst and state symbols.

A
128
Q

State the overall equation for the Contact Process. Include the catalyst and state symbols.

A
129
Q

How do heterogenous catalyst work?

A

By adsorbing reactants onto active sites located on their surfaces

130
Q

Describe catalyst poisoning

A

Impurities (in reaction mixture) bind to catalyst’s surface and block reactants from being adsorbed

131
Q

Explain how catalyst poisoning slows down the rate of a reaction

A

Catalyst poisoning reduces SA of catalyst available to reactants

132
Q

Explain why catalyst poisoning increases cost of chemical process

A
  • ∵ less product can made in certain time or with a certain amount of energy
  • Catalysts may need replacing or regenerated = costs money
133
Q

Name a substance that poisons the iron catalyst in the Haber Process

A

sulfur

134
Q

Explain how sulfur poisons the iron catalyst in the Haber Process

A
  • Hydrogen in Haber process is produced from methane
  • Methane is obtained from natural gas - contains impurities like sulfur compounds
  • Any sulfur not removed is adsorbed onto iron forming iron sulfide = stops iron catalysing reaction efficiently
135
Q

What are homogenous catalysts?

A

Catalysts that are in the same physical state as reactants

136
Q

Usually the homogenous catalyst is an _______ catalyst for a reaction between 2 aqueous solutions

A

aqueous

137
Q

Describe how homogenous catalysts work

A

Work by combining with reactants to form an intermediate species which reacts to form products and re-form the catalyst

138
Q

Why does the enthalpy profile for a homogeneously catalysed reaction contain 2 humps?

A

2 steps in reaction

139
Q

Activation energy needed to form intermediates is lower than…

A

that needed to make products directly from reactants

140
Q

______ reaction between iodide ions and peroxodisulfate (S2O82-) ions take place ________

A

Redox reaction between iodide ions and peroxodisulfate (S2O82-) ions take place very slowly

141
Q

Why does the redox reaction between iodide ions and peroxodisulfate (S2O82-) ions take place very slowly?

A
  • ∵ both ions negatively charged
  • Ions repel each other & so its unlikely they’ll collide and react
142
Q

State the equation for when iodide ions and peroxodisulfate ions react together

A
143
Q

Name a catalyst that speeds up the reaction between iodide ions and peroxodisulfate ions

A

Fe2+ ions

144
Q

Explain why adding Fe2+ ions speeds up the reaction between iodide ions and peroxodisulfate ions

A

∵ each stage of reaction involves a positive and a negative ion = no repulsion

145
Q

Describe and state the 1st equation that occurs when Fe2+ ions is added to iodide ions and peroxodisulfate ions. Include state symbols.

A

Fe2+ are oxidised to Fe3+ ions by S2O82- ions

146
Q

Describe and state the 2nd equation that occurs when Fe2+ ions is added to iodide ions and peroxodisulfate ions. Include state symbols.

A

Newly formed intermediate Fe3+ ions now easily oxidise the I- ions to iodine & catalyst is regenerated

147
Q

Mn2+ ions _________ the reaction between C2O42– and MnO4–

A

Mn2+ ions autocatalyse the reaction between C2O42– and MnO4–

148
Q

Explain what it meant by an autocatalysis reaction

A
  • A product of a reaction that acts as a catalyst for the reaction
  • Means that as a reaction progresses and the amount of product increases = reaction speeds up
149
Q

Write the overall equation for when Mn2+ ions autocatalyse the reaction between C2O42– and MnO4–

A
150
Q

Describe and state the 1st equation that occurs when Mn2+ ions is added to C2O42– and MnO4–. Include state symbols.

A

Mn2+ oxidised to Mn3+ by MnO4- ions

151
Q

Describe and state the 2nd equation that occurs when Mn2+ ions is added to C2O42– and MnO4–. Include state symbols.

A

Mn3+ reduced to Mn2+ (re-form catalyst ions) by C2O42- ions

152
Q

Draw [Cr(en)3]3+ & state its shape and co-ordination number

A

Octahedral & 6

153
Q

Draw [Co(en)2Cl2]+ & state its shape and co-ordination number

A

Octahedral & 6

154
Q

Draw two geometric isomers of [NiCl2(H2O)4]

A
155
Q

Draw two geometric isomers of square planar complex [PtCl2(NH3)2]

A

cis isomer = cisplatin

156
Q

Draw the two optical isomers of octahedral complex [Fe(C2O4)3]3-

A
157
Q

State the charge of :CN- ligand

A

-1

158
Q

State the charge of :OH- ligand

A

-1

159
Q

Draw the structure of the ethanedioate ion, C2O42-. Explain how this ion is able to act as a ligand. (2)

A

lone pair(s) on O– / O

160
Q

Draw the structure of the 1,2-diaminoethane (en)

A
161
Q

Give an example of complete ligand substitution when the co-ordination number and shape doesn’t change. Include the colour change & shape.

A
162
Q

Give an example of incomplete ligand substitution when the co-ordination number and shape doesn’t change. Include the colour change & shape.

A
163
Q

Give an example of complete ligand substitution when the co-ordination number and shape changes. Include the colour change & shape.

A
164
Q

Ligand Substitution

Write an equation where a monodentate ligand replaces a monodentate ligand e.g. with [Fe(H2O)6]3+ with CN-

A
165
Q

Ligand Substitution

Write an equation where a bidentate ligand replaces a monodentate ligand e.g. with [Cu(H2O)6]2+ and ethane-1,2-diamine

A
166
Q

Ligand Substitution

Write an equation where a multidentate ligand (that’s not a bidentate ligand) replaces a monodentate ligand e.g. with [Cr(NH3)6]3+

A
167
Q

When using potassium manganate(VII) in redox titrations with iron(II) ions it is essential that the reaction mixture is acidified. Explain why. (1)

A

ensures all MnO4- reacts to form Mn2+ / stop formation of MnO2 / becomes colourless

168
Q

Explain why an indicator is not needed in a redox titration with e.g. potassium manganate(VII) & iron(II) ions (1)

A

It’s self-indicating

169
Q

Suggest one reason why the colour of potassium manganate(VII) can be a source of error when using a volumetric flask to prepare a standard solution (1)

A

Difficult to see meniscus

170
Q

State the equation for when dichromate(VI) ions react with iron(II) ions

A

Cr2O72- + 14H+ + 6Fe2+ → 2Cr3+ + 7H2O + 6Fe3+

171
Q

Suggest one reason why electron pair repulsion theory cannot be used to predict the shape of the [CoCl4]2- ion (1)

A

Too many electrons in d sub-shell

172
Q

The redox reaction between acidified potassium manganate(VII) and sodium ethanedioate: Sketch a graph to show how the concentration of MnO4− ions varies with time in this reaction. Explain the shape of the graph. (4)

A
  • Starts slowly with low rate
    • ∵ -ve ions collide so high Ea​
  • Rate increases as autocatalyst (Mn2+) forms
  • Rate decreases as concentration of MnO4− ions / reactant(s) decreases (OR reactants are being used up)
173
Q

When the complex ion [Cu(NH3)4(H2O)2]2+ reacts with 1,2-diaminoethane, the enthaply change is appromimately zero. Suggest why. (2)

A
  • Cu-N bonds formed have similar enthaply/energy to Cu-N bonds broken
  • And same no. of bonds broken & made
174
Q

State the colour change for when iron(II) ethanedioate is titrated against potassium managante(VII) (burette)

A

Colourless to pale pink

∵ tiny excess of MnO4- (manganate(VII)) ions present

175
Q

Give 2 reasons why the use of a spectrometer is the most appropriate method for measuring the concentration of coloured ions (2)

A
  • Rapid determination of concentrations
  • Doesn’t use up any of the reagent
176
Q

Write an equation for the reaction that occurs between an aqueous solution of aluminium chloride and an excess of aqueous diaminoethane. Describe the appearance of the aluminium-containing reaction product. (3)

A

2[Al(H2O)6]3+ + 3H2NCH2CH2NH2 → 2Al(H2O)3(OH)3 + 3[H3NCH2CH2NH3]2+

White precipitate

A level Chemistry AQA Lewis (34 decks)

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