Transition metals
- Created by: ava.scott
- Created on: 10-03-15 14:33
View mindmap
- Transition Elements
- Definitions
- D-block element
- An element with its highest energy electrons in d-orbitals.
- Transition metal
- An element which can make ions with partially filled d-orbitals.
- Complex ion
- A transition metal ion bonded to one or more ligands by coordinate bonds,
- Ligand
- A molecule that can donate a pair of electrons to a bond with a transition metal.
- Coordination number
- Total number of coordination bonds
- Ligand subsitution
- a reaction in which one ligand in a complex ion is replaced by another.
- D-block element
- Exceptions in d-block elements
- Chromium
- 1s2 2s2 2p6 3s2 3p6 4s1 3d5
- Cobalt
- 1s2 2s2 2p6 3s2 3p6 4s1 3d10
- Scandium and Zinc
- Scandium only forms the 3+ orbital, where all the d-orbitals are empty.
- Zinc only forms the 2+ ions, where all d-orbitals are full.
- Chromium
- PROPERTIES
- Physical
- shiny
- high density
- high melting and boiling points
- good conductors in solid form
- Chemical
- Coloured compounds
- Variable oxidation states
- Good CATALYSTS
- Haber process
- Makes NH3 (ammonia) from N2 and H2
- Uses iron as a catalyst
- Contact Process
- Coverts SO2 into SO3 when manufacturing H2SO4
- Uses Vanadium (V) Oxide
- Hydrogenation of alkenes
- Saturates double carbon binds with hydrogen.
- Nickel catalyst at 150 degrees
- Decomposition of H2O2
- Makes water and oxygen
- Manganese (IV) Oxide
- Haber process
- Physical
- Precipitation reactions
- Soluble ions mixed to make an insoluble product.
- With hydroxides
- Cu2+
- Pale blue solution to pale blue precipitate
- Co2+
- Pale pink solution to make a blue ppt, which turns beige in air.
- Fe2+
- Green solution to green ppt, which goes red in air.
- Fe3+
- Yellow solution goes to a red ppt.
- Cu2+
- COMPLEX IONS
- SHAPE
- most common is octahedral shape.
- 6 dative bonds
- bond angle is 90 degrees.
- e.g. [Fe(H2O)G]2+
- most common is octahedral shape.
- STEREOISOMERSIM
- TWO TYPES
- Cis Trans
- cis platin
- [Ni(NH3)2(CL)2]
- CIS isomer can be used as a cancer drug
- Cis platin binds to DNA preventing replication, and therefore cell division. This tops tumours from growing,
- SQUARE PLANAR SHAPE
- CIS= same groups/ligands are on the same side or plane.
- Trans- when the same groups are on different sides/planes
- cis platin
- optical
- non-superimposable mirror images
- Cis Trans
- Species with the same structural formula but a different arrangement of atoms in space.
- TWO TYPES
- LIGANDS
- Monodentate
- Can make one coordinate bond with a transition metal ion
- e.g H2O
- BiDentate
- Can make two coordinate bonds with transition metal ions
- e.g. ethane-1,2-diamine (NH2CH2CH2NH2) or ethandioate (C2O4^2-)
- hexadentate
- Makes six coordinate bonds with an transition ion
- e.g. EDTA
- Monodentate
- LIGAND SUBSITUTION
- With chloride ions
- Cu2+ goes from a pale blue solution to a yellow solution
- Co2+ goes from a pink solution to a pale blue solution.
- Chloride ions are bigger so usually form 4 coordinate bonds only.
- with ammonia
- Cu2+ gos from a pale blue solution to a light blue precipate Cu(OH2) to a deep blue solution [Cu(NH3)4(H2O)2]2+
- Co2+ will first form a light blue ppt (Co(OH)2) left in air to make a beige precipitate.
- HAEMOGLOBIN
- Haemoglobin cantains a haem grouo with has iron in it.
- Oxygen binds to the haem group. Ligand substitution allows the oxygen to be released and obtained in appropriate circumstances (e.g. in lungs it would pick up)
- Haemoglobin cantains a haem grouo with has iron in it.
- STABILITY CONSTANTS
- products over reactants
- don't include water
- The larger the stability constant, the more stable the complex.
- don't forget units!
- With chloride ions
- SHAPE
- REDOX TITRATIONS
- equations to know
- MnO4-
- HCl cannot be used as it reacts with MnO4-
- +5e- + 8H+
- Mn2+ + 4H2O
- 2S2O3(2-)
- thiosulphate equation!
- + I2
- 2I- + s4o62-
- 2Cu2+
- + 4I-
- 2CuI + I2
- + 4I-
- Cr2O7(2-) +
- 6e- + 14H+
- 2Cr3+ 7H2O
- 6e- + 14H+
- MnO4-
- equations to know
- Definitions
Comments
Report