Transition Metals Flashcards by Thomas McNamara

Define Transition Metal

Metal atom with partially filled d subshell

How well did you know this?

Not at all

Perfectly

What transition metals do we cover?
What is an exception that isn’t a transition metal?

Top row Sc-Zn
Zn exception 3d10 subshell for atoms & ions

How well did you know this?

Not at all

Perfectly

How do transition metals form complexes?

Forms coordinate bond with ligand from e-s from ligand for dative bond

How well did you know this?

Not at all

Perfectly

Define a Ligand

Particle with lone pair that forms a co-ordinate bond with metals

How well did you know this?

Not at all

Perfectly

Define a Complex

Metal ion + ligand with a co-ordinate bond

How well did you know this?

Not at all

Perfectly

Define co-ordination number

Number of co-ordinate bonds in a complex

How well did you know this?

Not at all

Perfectly

Define a Lewis Base

Lone pair donor

How well did you know this?

Not at all

Perfectly

Define a Lewis Acid

Lone pair acceptor

How well did you know this?

Not at all

Perfectly

What shapes do 4 co-ordinate bonds make? Outline their angles

Tetrahedral = 109.5°
or
Square Planar = 90° & 180°

How well did you know this?

Not at all

Perfectly

What shape do 6 co-ordinate bonds make? Outline the bond angles

Octahedral = 90° & 180°

How well did you know this?

Not at all

Perfectly

What shape do 2 co-ordinate bonds make? Outline the bond angles

Linear = 180°

How well did you know this?

Not at all

Perfectly

What type of ligand forms 2 co-ordinate bonds? Outline both of their names

Bidentate ligands/ Chelating ligands

How well did you know this?

Not at all

Perfectly

Outline the Chelate effect

A metal ion increases in stability when a chelating ligand bonds to a metal ion forming one or more rings
Entropy also increases

How well did you know this?

Not at all

Perfectly

Outline the equation for entropy with units

ΔG = ΔH - TΔS
If ΔG is - then feasible
ΔG = Δ in Gibbs free energy (kJmol-1)
ΔH = Δ in enthalpy (kJmol-1)
T = Temperature (K)
ΔS = Δ in Entropy (JK-1mol-1)

How well did you know this?

Not at all

Perfectly

Outline all the complimentary colours

Red & Green
Purple & Yellow
Blue & Orange

How well did you know this?

Not at all

Perfectly

How do transition metals form coloured ions?

They absorb different wavelengths of light and reflect their complimentary colours

How well did you know this?

Not at all

Perfectly

Outline 3 multidentate ligands and the number of ligands they have

Ethane dioate = 2 ligands (X2 :O-)
Haemoglobin = 6 ligands
EDTA = 6 ligands (2 :N- + 4 :O-)

How well did you know this?

Not at all

Perfectly

What does the colour of the transition metal ion depend on?

The metal ion
The Type of ligand attached
The co-ordination number
The oxidation state of the transition metal

How well did you know this?

Not at all

Perfectly

What happens to transition metal d orbitals when ligands bond?

When ligands bond 5 d orbitals don’t have same energy
e- excited from lower d orbitals to higher d orbitals

How do coloured ions form?

Different energy of d orbitals is in the UV/Visible region -> d-d

Outline the Planck equation with units

E diff between 2 d-d orbitals (J) = Planck’s constant (6.63x10-34 Jhz-1) X frequency (hz)
E diff = hf

Outline the variable oxidation state use in Tollen’s reagent

Has [Ag(NH3)2]+
Ag (+1) reduced to Ag (0)

Outline the variable oxidation state use in Fehling’s solution

Contains Cu (+2) reduced to Cu (+1)

Outline the variable oxidation state use in acidified potassium dichromate

Has Cr2O7^2- ions
Cr(+6) reduced to Cr(+3)

Outline the variable oxidation state use in redox titrations

e.g: acidified KMnO4 used to analyse Fe2+

Outline the coloured ions of MnO4-, Mn7+, and Mn2+

MnO4- = Purple Mn7+ = Purple Mn2+ = Purple pink

How do pH & ligands affect redox reactions?

Reduction of V (+5) to V(+2) due to an acid with Zn

Outline all the colour stages of Vanadium

V(+5) VO2 = Yellow V(+4) VO^2+ = Blue V(+3) V3+ = Green V(+2) V2+ = Violet

Outline the anagram for the colour change of V

You Better Get Vanadate

Outline the colours of Fe2+ & Fe3+

Fe2+ = green Fe3+ = brown

Outline how redox potentials impact oxidation states of transition metals

Lower O2 state = Reducing agent in acidic conditions Higher O2 state = Oxidising agent in alkaline conditions

Define complete ligand substitution

Substitution of similar sized ligands -> entropy is the =

Define Partial ligand substitution

Substitution of different sized ligands -> entropy changes

Define Heterogeneous catalyst

Catalysts in different phase to reactants (usually solid e.g: C2H4 + H2 -> C2H6

Define homogeneous catalysts

Catalysts that are the = phase as reactants (normally aq)

Define Adsorbed

Forms bond to the atoms in solid surface

Outline how Heterogeneous catalysts work in 3 steps

1. Reactants adsorbed onto surface - Weakens bonds - brings molecules closer - more favourable orientation 2. Reaction takes place 3. Products desorbed (leave surface)

Outline how too strong of an adsorption impacts heterogeneous catalysis

Too strong (e.g Tungsten/W) - Reactants can't move round surface -Products can't desorb

Outline how too weak of an adsorption impacts heterogeneous catalysis

Reactants not adsorbed (e.g: silve/Ag)

Outline ideal adsorption for heterogeneous catalyst

Nickel and Platinum

Outline the characteristics of heterogeneous catalysts

Large SA Spread thinly over ceramic honeycomb

Outline the reacting ratio for the redox titration of Fe^2+ ions to MnO4- ions

Fe : MnO4- 5 1

Outline the reacting ratio for the redox titration of C2O4^2- ions to MnO4- ions

C2O4^2- : MnO4- 2.5 1

Outline the steps in the % by mass calculations of redox titrations

1. Find the reacting ratio 2. Find the moles of the reagent with the ratio of 1 (n=cv) 2. Multiply this by the larger ratio to find the moles of the desired reagent 3. Find the moles in the total volume 4. Find the mass of the desired substance 5. Find the % by mass (desired/total X 100)

Outline an example of homogeneous catalysis

Reaction of: MnO4- + C2O4^2- Both -ve so repulsion = large Ea to overcome Fe2+/Fe3+ reduces Ea