Module 1-6 Flashcards
Ground state
Most stable electron configuration
Electrons in lowest energy state
Hunds rule
For degenerate orbitals, orbitals of same energy level), the lowest energy is obtained when the number of electrons with same spin is maximised
Tranisition metal ions
Lewis acids
Cations
Have vacant d orbitals
Electron acceptors
Effective nuclear charge
Electrons in inner shell have shielding effect on electrostatic attraction between protons and electrons in outer shells
Zeff trend
Increases across the row
Decreases in order of s>p>d>f
Atomic radii
Half distance between metallic nuclei
Increases down a column
Decreases across row
Anion atomic radii
Larger than parent atom
Cation ionic radii
Smaller than parent atoms
Electronegativity
Increases across row and decreases down column
Ionisation energy
removal of electron from highest occupied orbital of neutral atom
Follows rules same as atomic radii
Chlorophyll
Green compound found in leaves and stems
Channels sunlight into chemical energy which drives biochemical reactions through the process of photosynthesis
Chlorophyll structure
Tetrapyrrolic ring
Conjugated double bond system
Central magnesium atom
Hard Lewis bases
Donor atom is small and highly electronegative
Soft Lewis base
Donor atom is larger less electronegative making its electrons more polarisable
Hard Lewis acids
Either noble gas configuration or high charge and strongly held electrons
Soft Lewis acids
Large number of d electrons and low charge
More polarisable electrons
Ligand field stabilisation energy
Pt(2) > Ni(2) > Co (2) > Cu(2) > Fe(2) > Zn (2) > Mg(2)
Lewis bases
Substance that act as electron pair donors
Lewis acids
Substances that act as electron pair acceptors
Transition metal complexes
Complex is a combination of a Lewis acids and Lewis base
Ligand forms coordinate covalent bond to central metal ion
Neutral ligands
H20
NH3
CO
Anionic ligand
OH - Cl- Br- I- CN-
Bidentate ligands
En
Polydentate
EDTA 4-
Ligands
Lewis bases
Have atleast one non bonded pair of electrons
Chelate
Claw agents
Can bind to metal in two or more places
Counter ions
Written on outside of square brackets and not bonded to metal ion
Negatively charged - right
Positively charged - left
Coordination atoms
Number of ligand donor atoms bonded to metal ion
Charge of metal complex
Sum of charge on metal ion and sum of ligand charges
Oxidation state
Charges on metal atom
Complexes containing neutral ligands the oxidation state is equal to the net charge on complex
Linear
Coordination number is 2
Tetrahedral or square planar
Coordination number is 4
Octahedral
Six coordination complexes
Factors influencing stability of metal complexes
Irving Williams series of stability
Hard soft acid base theory
Chelate effect
KF
Formation constant