Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry a level > U2 S4-Transition metals > Flashcards

U2 S4-Transition metals Flashcards

1
Q

Transition Metals

A

Metal that can form one or more stable ions with an incomplete d subshell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

rules of electron configuration

A

1- e- fill the lowest energy sub-levels first

2-e- fill orbitals before sharing orbitals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

4s sub-shell fills up before 3d sub shell

A

4s sub-shell has a lower energy level than 3d sub-shell despite having a higher principal quantum number

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

which 2 elements deviate from the electron configuration rules

A

Chromium (Ar) 3d5, 4s1 = 1e- in each orbital of 3d sub-level + 1 in 4s sub-level is more stable
Copper (Ar) 3d10, 4s1 = full 3d sub-level + 1e- in 4s sub-level is more stable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Physical properties of Transition metals

A

1-High density

2-High MP and BP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Chemical properties of Transition metals

A

1-form complex ions
2-form coloured ions
3-good catalysts
4-can exist in variable oxidation states

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Transition metal ions are removed first from

A

4s e- removed first before 3d e- sub-level

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which 2 3d sub-level elements are nor transition metals

A

Sc (Ar) 4s2,3d1 - (Sc3+) loses 3e- (Ar)

Zn (Ar) 4S2, 3d10 - (Zn2+) loses 2e- (Ar) 3d10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Why Sc and Zn not transition metals

A

Sc forms (Sc3+) - empty 3d sub-level
Zn forms Zn2+ - full 3d sub-level
Zn2+ and Sc3+ are the only stable ions formed
-dont form incomplete sub-levels that cause transition metal chemical properties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why transition metals show variable oxidation states

A

The energies of the 4s and 3d sub-levels are similar so e- gained or lost using similar amounts of energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

chemical properties of transition metals caused by

A

the incomplete 3d sub-level electron configuration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Physical properties of an element determined by

A

the atomic mass (Ar) of the atom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Chemical properties of an element determined by

A

electron configuration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Complex ion

A

metal surrounded by co-ordinately bonded ligands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Co-ordinately bond

A

covalent bond in which both shared e- pairs are donated from the same atom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

ligands

A

atom, ion or molecule that donates a pair of e- to a central positive metal ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

monodentate

A

ligands that can only form one co-ordinate bond with central metal ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Multidentate

A

ligands that can form more than 2 co-ordinate bonds with central metal ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Bidentate

A

ligands that can form 2 co-ordinate bonds with central metal ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Oxidation state of central metal ion =

A

= total charge of complex- sum of charges of the ligands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Co-ordination number

A

Number of co-ordinate bonds between the ligands and central metal ion

22
Q

6 co-ordinately bonded ligands shape

A

1-octahedral

23
Q

4 co-ordinately bonded ligands shapes

A

1-tetrahedral

2-square planar

24
Q

2 co-ordinately bonded ligands shapes

A

1- linear shape

25
Q

Small ligands types and co-ordination number

A
  • H2O + NH3
  • 6 co-ordination number
  • Octahedral
26
Q

large ligands types and co-ordination number

A
  • (Cl-)
  • 4 co-ordination number
  • Tetrahedral
27
Q

stereoisomerism

A

has same structural formula different arrangement of atoms in space

28
Q

Optical isomerism/ Enatiomers

A

same structural formula but with 4 different groups arranged around a chiral C atom so its a non-superimposable mirror image of the other molecule

29
Q

optical isomerism occurs in

A

octahedral complexes with 3 Bidentate ligands

30
Q

Cis-Trans isomerism

A

-Type of E/Z isomerism with 2 groups attached to C atoms around C=C double bonds are the same

31
Q

Cis-Trans isomerism in square planar complex ions

A 
cis= 2 pairs of ligands next to each other 
trans= 2 pairs of ligands opposite each other
32
Q

Cisplatin

A

PtCl2(NH3)2 - same group next to each other

33
Q

Cisplatin uses

A

1- treats cancer by stopping DNA unwinding so semi-conservative replication can’t occur stopping tumours reproducing new cells
2-mechanisms triggered that cause cell death

34
Q

Cis-Trans Isomerism of Octahedral complex ions (6)

A
  • occurs in 4 ligands of one type and 2 ligands of another type
  • 2-ligands opposite= trans
  • 2 ligands next = Cis
35
Q

Negative effects of Cisplatin

A

1- can bind to normal cells that replicate quickly like hair stopping them from replicating causing hair loss, suppress immune system.
2- damages Kidneys

36
Q

How to lessen side effects of Cisplatin

A

1- Very low dosages

2-targeting cancer cells directly that only attacks healthy cells

37
Q

Why is Cisplatin as cancer treatments used despite adverse effects

A

balance of positive long term affects out weigh negative short term effects

38
Q

Ligand Substitution reaction

A
  • at least 1 ligand swapped for another ligand

- results in colour change

39
Q

Substitution of similarly sized ligands

A
  • ligands same size
  • co-ordination number of complex ions remains the same
  • Shape stays the same
  • colour changes
40
Q

Substitution of different sized ligands

A
  • ligands different sizes
  • co-ordination number of complex ion changes
  • shape changes
  • colour changes
41
Q

Partial substitution of Ligands

A
  • some ligands substituted partially
  • not all ligands substituted
  • colour changes
42
Q

Ligand exchange reactions can be easily reversed unless

A

unless the complex ion produced is much more stable than the old one

43
Q

if new ligands form stronger bonds with the central metal ion than the old ligands

A

change is less easy to reverse as new complex ion more stable

44
Q

Multidentate ligands form more stable ion complexes than monodentate ions so

A

the ligand exchange involving bidentate and multidentate ligands are hard to revers.

45
Q

Ligands in order of most stable to least

A

1- multidentate = most stable
2-bidentate
3-monodentate = least stable

46
Q

Enthalpy change for a ligand

A

1- very small

2-because the strength of the bonds being broken is similar to the strength of the new bonds being made

47
Q

Entropy change for a ligand

A

1-when monodentate ligands are substituted by multi and bidentate ligands the number of particles increases
2-the more particles, the greater the entropy so reactions are more likely to occur
3-multi and bidentate are more stable than monodentate ligands
4-chelate effect

48
Q

chelate effect

A

1-when monodentate ligands substituted by bidentate and multidentate ligands it forms a more stable ion complex
2- particles number increases
3-entropy of system increases without enthalpy changing significantly
4-

49
Q

when multidentate ligand is substituted by bidentate or monodentate ligands

A

1- more stable complex ion formed
2-particle number increases
3-so entropy of system increases to a large and positive value without enthalpy changing significantly
4- AG decreases below zero so reaction feasible
AG=AH-TAS

50
Q

Haeamoglobin

A

Fe(N)5(H2O) —Oxygen—-> Fe(N)5(O2)

deoxyhaemoglobin

Chemistry a level (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions