(21) Acids & pKa In Organic Chemistry Flashcards
under what two conditions is a solution in equilibrium ?
- forward and backwards rate of reaction are equal
2. concentrations remain constant
what does pH measure
the acidity of a solution of acid DEPENDING on its concentration
what is pKa
the property of a compound that measures the ability to dissociate a proton
two factors that effect acid strength
- strength of A-H
2. stability of the conjugate base ( A- )
how does resonance effect the stability of an acid ?
stabilises the negative charge on the conjugate base, therefore making it more acidic
describe how inductive effects modify the strength of an acid ?
- anions with electron withdrawing groups attached ( F, Cl etc ) is stabilised
- this favours acid dissociation
define pH
the measure of hydrogen ion concentration
define pKa
is obtained by the ionisation constant of a molecule to identify the acid strength