Acids & bases Flashcards
Brønsted-Lowry acid:
Proton donor
Brønsted-Lowry base:
Proton acceptor
Conjugate acid-base pair:
Contains 2 species that can be interconverted by transfer of a proton.
Arrhenius model of acids and bases:
Acids dissociate & release H+ in aq solution
Alkalis dissociate & release OH- in aq solution
{{ bronsted-Lowry model extends this to emphasise role of proton transfer}}
Monobasic, dibasic, tribasic, refer to:
{{monoprotic, diprotic, triprotic}}
Total no of H+ in the acid that can be replaced per molecule in an acid-base reaction.
E.g. HCl = monobasic
CH3COOH = monobasic
H3BO3 = tribasic
H+ (aq) is a simplified form used instead of:
H3O+ (aq)
Hydronium ion
Spectator ions:
They do not react during a chemical reaction. Their oxidation state & state of matter remains unchanged.
What type of scale is pH scale?
Logarithmic
pH = ?
Log formula
-log [ H+ (aq) ]
Reverse:
[ H+ (aq) ] = 10^-pH
Ka is ______ constant.
Acid dissociation
Is one of several special equilibrium constants used for acid-base equilibria. All constants are just versions of the equilibrium constant Kc.
Ka formula
Involves pKa
Ka = 10^-pKa
Reverse:
pKa = -log(Ka)
This formula shows dissociation of any weak acid:
HA (aq) H+ (aq) + A- (aq)
Formula for calculating Ka:
Ka =
[H+ (aq)] + [A- (aq)]
_____________________
[HA (aq)]
Units are always mol dm-3
The stronger the acid, the _____ the Ka value and the ______ the pKa value.
Larger
Smaller
