Hoorcollege 5 – 6 maart 2023
Ph is an identification for how many we have in a solution.
Aspirin in its neutral form shows poor solubility in water
Codeine also Neemt H op more soluble in water
- Having a lot of proton is low ph, smaller than 7
Differences in protonation state (charge) can be used to separate compounds
- Water laag en organische laag
Repeat lewis structure:
- Electron movement from nucleophile to electrophile
Correct orbital overlap is essential for successful chemical reactions
- Without a good overlap there is no reaction
How more similar energy between HOMO and LUMO, the easier the reaction will verlopen
- All other orbitals have no influence on the reactivity
Hoe minder verschil tussen levels hoe meer energy gain. Heeft invloed: the larger a
compound's HOMO-LUMO gap, the more stable the compound.
Energy gain is maximized when the difference between
HOMO and LUMO small is:
- HOMO of the nucleophile is relative high in energy
- LUMO of the electrophile is relative low in energy
Een h2o molecuul is niet lineair door de vrije elektronenparen op de O. De hoek is 104
graden en dit is kleiner dan 109 graden van sp3 orbital. Omdat elektronen meer ruimte in
beslag nemen dan h
Many drugs are salts of organic compounds
Hydronium ion as h30+
Hydroxy ion (OH-)
Acid: ionizes to give H+ in H20
Base: ionizes to give OH- in H20
- Slechte definitie, want uitzonderingen?
, o Arrhenius definition of acids and bases is
not enough to describe whats happening
Base + acid conjugate acid + conjugate base
Acid is a proton donor, base a proton acceptor betere definitie (bronsted)
Water is partially ionized:
- Water can act as a base and a acid.
Ph is the negative logarithm of the H+ concentration
Hoe hoger de ph, hoe sterker de base
Hoe lager de ph, hoe sterker het zuur
PKa is the negative logarithm of the equilibrium constant for the dissociation of the acid HA
Small pka values mean there are strong acids.
Large pka values are strong bases