Biology: Biochemistry TPR Review Acids & Bases Flashcards
Acids (Bronsted Lowry) Def
Proton (H+) donors
Bases (Bronsted Lowry) Def
Proton (H+) acceptors
conjugate base trick
one less H atom and one more - charge than the acid that formed it
Conjugate acid trick
one more H atom and one more + charge than base that formed it
Strength of an acid is related to:
How much of the products are favored over the reactants
Ka/kb
acid/base-ionization (acid or base-dissociation constant) - determines relative strengths of acids
The larger the Kb or Ka value (and vise versa)
the stronger the base or acid
amphoteric
acts as acid or base (like water)
Formula for pH
pH = -log[H+], where [H+] = 10^-ph
[H+] = ^-7
neutral ph (pure water)
[H+] > ^-7
ph is less than 7 and is acidic
[H+] < ^-7
ph is greater than 7 and is basic
low ph means high :
H+, acidic
High ph means low:
H+, basic
Formula POH
POH= -log[OH-], where [OH] = 10^-POH
formula of PH and POH
PH + POH = 14
Pka and Pkb formula
Pka = -logKa Pkb = -logKb
“P” means
take the negative log of
Ka and Pka values are opposite. Explain
The > the Ka value, the stronger the acid. The lower then Pka value, the stronger the acid.
When a acid or base is stronger, what happens chemically?
More molecules dissociate into ions in aqueous solution
Buffers
solution that resists changing pH when acid or base amounts are added
Most important buffer system in blood plasma (and for the MCAT)
bicarbonate buffer system
H2CO3 –> H+ + HCO3-
