-
SA WB salt
- soln will be acidic
- weak base results in a stronger conjugate acid so that ion will make soln more acidic
-
SB WA
- soln will be basic
- WA will give a stronger base that'll make soln more basic
-
WA WB
state of soln depends on Ka and Kb, whichever is larger
-
SB SA
- neutral pH
- both ions in the salt will be non reactive cus they're both from strong species
-
relationships
- Kw=KaKb=1x10^-14
- pH+pOH=14
- pH=-log[H]
- [H]=10^-pH
- pKa= -logKa
- pKa + pKb=pKw=14
-
pKa and Ka relationships
- the larger the Ka, the smaller the pKa
- the larger the Ka, the stronger the acid
- the smaller the pKa, the stronger the acid
-
acid-base tit.
- if both strong, equiv point at neutral
- WA SB, equiv point pH basic
- Wb SA, equiv point pH acidic
-
half-equiv point
- the point where [HA]=[A-]
- as the base is being added, the acid is dissociating and creating a buffer as the [A-] goes up
-
equivalence point
the point where all moles of HA are neutralized/used
-
buffer
- resists extreme changes to pH by alternating btwn its acid and conjugate form
- ideal buffers have equal concentrations and so pH=pKa
-
henderson-hechlbach
pH=pKa + log[A-]/[HA]
|
|
