Transition Elements 5.3.1 Flashcards
What is a Transition Element?
Elements that have one or more stable ion with partially filled d sub-shells
What are properties of Transition Metals?
High melting point High boiling point Denser than s-block Conductive Poscess strong metallic bonds
What happens when Transition Elements react?
They lose electrons from the 4s sub-shell first
Are Sc and Zn Transition Elements?
No because they don’t form ions with partially filled d sub-shells
What colour are Chromium ions?
3+:
Green
6+:
Orange (seen in dichromate)
What colour are Manganese ions?
2+:
Pink
What colour are Iron ions?
2+:
Green
3+:
Orange
What colour are Copper ions?
2+:
Blue
Define adsorption?
When something sticks to the surface of a material
Define absorption?
When something when something enters another material
How does Iron act as a catalyst for the Haber Process?
Iron offers an alternative path of reaction.
1) H2 and N2 are adsorbed onto the surface of the iron.
2) H-H and N-N bonds weaken.
3) Bonds are formed between H and N
4) Ammonia molecule desorbs from the iron
Examples of Catalysts and their reactions?
2SO3 + O2 ⇌ 2SO3
Uses V2O5 as a catalyst
Alkene +H2 → Alkane
Uses a Nickel or Platinum catalyst
What is a Complex Ion?
A Complex ion consists of a central positive ion surrounded by ligands
What is a Ligand?
A species that can donate one or more lone pairs to form diative bonds
What is a Co-ordination Number?
The number of diative bonds formed in a complex ion
Examples of Ligands?
H2O
NH3
Cl-
What are the three types of Ligand?
Monodentate:
Can donate one lone pair
Bi-dentate:
Can donate two lone pairs (eg. NH2CH2CH2NH2, en)
Multidentate:
Can donate three ore more lone pairs (eg.EDTA)
What shape are complex ions?
Tetrahedral
Octahedral
Square plannar
What is Steroisomerism?
When two molecules have the same composition but different layout
What are the two types of Stereoisomerism?
Cis:
The different ligands are next to each other
Trans:
the different ligands are opposite each other
What is an example of a molecule with Stereoisomerism?
Cisplatin
It can act as a cancer drug
What is Opticalisomerism?
When molecules that have the same composition.
But structures are mirrors of each other so cannot be reoientated to looke the same.
What is a Haem group?
It is a complex ion within the structure of Haemoglobin
What is the purpose of the Haem group?
To hold oxygen
Why does Cyanide and Carbon Monoxide prevent a Haem group from working?
They react with the iron at the centre more strongly than oxygen
What is Ligand Substitution?
Reversible reaction where a complex ion change some of its ligands
What happens during the Ligand Substitution of Copper(ii)?
Copper and Water complex ion has a small amount of ammonia added to it, which produces copper hydroxide precipitate.
A large amount of ammonia is then added to produce a Copper with 2Waters and 4Ammonias as a complex ion.
lots of water being added returns to Copper and Water complex ion.
What happens in the Ligan Substitution of Chromium(iii)?
Chromium and Water complex ion+ NaOH gives Chromium Hydroxide.
Chromium Hydroxide + Excess NaOH gives Chromium and 6 hydroxide ligands.
excess of water returns to Chromium and Water complex ion
What is the Oxidising Agent For Fe2+ and (Cr2O7)2-?
(MNO4)-/H+
Acidifed Manganate
What are Reducing Agents for Cu2+?
I-
Iodide
Zn/H+
Acidified Zinc
Why is Cu+ a colourless solution?
It has not got any partially filled d sub-shells
