N330 final
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- coordination #6
- most common for TM (d-0 to d-9) -octahedral
- coordination #7
- trigonal pentagonal
- coordination #8
- cubic, dodecahedron
- coord number 9
- tricapped trigonal prismatic
- coordination #4
- very common for TM complexes -tetrahedral (early TM -- d-10) - square planar (d-8 complexes)
- coodination #5
- trigonal bipyramidal (most common when ligands are same) - square pyramidal (common when one ligand is unique)
- penetrating power for the 3 emissions
- alpha: .03 mm beta: 2 mm gamma: 10cm
- in beta decay...
- a neutron is converted into a proton and an electron is expelled.
- binding energy
- the force required to overcome the proton-proton repulsions and allow the nucleus to be stable
- all radioactive decays are:
- first order b/c, to occur, there needs to be one and only one reactant. The reaction involves only the nucleus of the atom.
- acidic oxides
- on dissolution in wter, these bind to a water molecule and release a proton (donor)
- basic oxides
- an oxide to which a proton is transfered (acceptor)
- conjugate base
- a species with one fewer proton than the parent acid
- conjugate acid
- a species with one mmore proton than the parent base
- diastereomers
- are stereoisomers that have diff configurations at one or more chiral centers
- 6 coord: MA4B2
- can form cis and trans (B's)
- 6 coord: MA3B3
- can form meridinal and facial
- 6 coord: MA2B2C2
- all trans, all cis (delta and Lambda (2)), 1 trans and 2 cis (3 of these)
- chelate related to stability
- - increasing size of chelate increases the stability of the complex - increase in ring size decreases the stability of the complex
- 3 substitution mechanisms:
- associative, dissociative, interchange reaction
- associative substitution
- incoming base adds before the LG leaves. incoming ligand is very important
- dissociative substitution
- LG leaves and new ligand adds at the same time. incoming ligand is not that important
- trans effect
- the effect of a coordinated ligand upon the rate of substitution of ligands opposite to it.
- what can inhibit associative mechanism
- steric crowding
- nitrogenase is an enzyme that contains:
- 2 proteins: the larger MoFe-protein & the smaller Fe-protein
- MoFe protein contains:
- part of nitrogenase!! 2 types of a super cluster: P-cluster: which transfers electrons & FeMoco cluster: which is the catalytic site of NH3
- Fe-protein
- part of nitrogenase -> its role is to transfer electrons to the MoFe-protein
- hydrogenase physical description:
- have fragile active site burried deep in the enzyme, thus necessitating special poors and FeS cluster for long range ET.q
- 2 types of hydrogenase:
- FeFe-hydrogenases &NiFe-hydrogenase
- FeFe-hydrogenase
- tend to operate in direction of H2 production - found in strictly anaerobic organisms only
- NiFe-hydrogenase
- catalytically active form assigned as Ni(III)-H(-)
- Fe-overload treatment
- chelation therapy is used by admistering a ligand to separate Fe from tissues allowing it to be excreted.
- Cancer treatments
- -cisplatin: designed to stop the growth of cancer cells. This has a lot of neg sideeffects so, carboplatin is also used. - bleomycin: binds to DNA and creates a ferry species that oxygenates sites and leads to degredation.
- Anti-Arthritus drugs
- -commonly use Au - myochrisin and solganol and auranofin are types
- myochrisin
- treats arthritus, features Au(I) with linear coordination. cannot be given orally due to hydrolysis in the stomach
- solganol
- helps treat arthritus but cant be given orally due to hydrolysis in the stomach
- auranofin
- helps treat arthritus and can be given orally.
- complexes that target the heart
- cationic
- complexes that target the brain
- neutral
- complexes that target the kidney
- anionic
- nuclear reactions
- AKA transmutations; conversion of an unstable (parent nucleus) to a more stable (daughter) with spontaneous emission of radtiation
- smoke detectors
- use americium-241 which is absorbed by smoke, which in turn sets off the alarm
- blue copper in PC
- terminal electron acceptor in photosynthesis
- horseradish peroxidase
- scavenges free hydrogen peroxide and forms compound I and II reaction: H2O2 + 2e-+2H+ --> 2H2O
- Cyt c Oxidase
- creates proton gradient across membrane - ET: Cytc --> CuA --> heme a --> binuclear site reaction: O2 + 4e- + 8H+ --> 2H2O +4H+
- oxygenases (Cyt P450)
- reaction: R-H +O2+ 4e- +2H+ --> ROH + H2O
- reductive elimination
- reduction of metal by 2e- and release of substrate
- transmetallation
- using a second metal-alkyl species to deliver the second coupling partner to the active metal center and remove a halide from the catalyst.
- trans to cis isomerization
- isomerization of the ligands on the metal center which changes the groups to be coupled so they are cis to one another, without this, reductive elimination cant occur
- oxidative addition
- addition of substrate oxidizes the catalyst by 2e- by adding the R-x substrate to the metal center
- peroxidases
- peroxidases catalyse reduction of harmful hydrogen peroxide. Also produces Fe(IV) as an intermediate which is vital in numerous biological processes.
- oxidases
- enzymes that catalyse the reduction of O2 to water or H2O2 without the incorporation of O atoms into the oxidizable substrate.
- oxygenases
- catalyse the insertion of one or both O atoms derived from O2 into an organic substrate.
- monooxygenases
- catalyse the insertion of one O atome while the other atom is reduced to to H2O
- dioxygenases
- catalyse the incorporation of both O atoms.
- Fe(IV)
- used to cleave an O-O bond. - in one step there will be Fe-O-O with Fe being something other than (IV) then, in the next step it will be Fe(IV)=O
- values of L and what they correspond to, and how it relates to n
- L=0,1,2,...(n-1) L=1-->p 0-->s 2-->d 3-->f
- ml=
- -l....0....+l
- n= l= ml=
- n=which shell l= subshell ml= orbital
- effective nuclear charge
- explains that since the inner core electrons are btw the outer electrons and the nucleus, they shield the outer electrons (screening effect) from the full positive charge.
- EA explained with atomic radii
- the smaller the atom, the closer a new electron can get to the nucleus and the stonger the attraction between them.
- IE example
- an element's change in IE will be moderate until it reaches a noble gas then it will spike quickly bc it doesnt want to lose another electron
- cations always have what in relation the their neutral form
- cations are always smaller than their neutral form while anions are always bigger
- what happens to delta G and Ecell when coefficients are doubled in a rxn
- delta G changes but Ecell stays the same (independent of scale)
- calculating delta G
- G=-nFEcell
- calculating standard equilibrium constants
- Ecell=RT/nF*ln(K) --> K=e^nFEcell/RT **these are done when conditions are not standard
- nernst equation
- calculate the cell potential for redox reactions under nonstandard conditions: Ecell=E(o)cell-(RT/nF)lnQ
- calculating Ecell with different concentrations
- Ecell=E(o)cell-(RT/nF)*log(conc products/conc reactants) **make sure to include coefficients
- leveling effect
- brings all acids down to the acidity of H3O+ (ex. water)
- factors that determine rate of association/dissociation
- 1. metal centers with high ox numbers will have stronger bonds to ligands than metal centers with low ox numbers 2. steric hinderance will slow down the rate of association.