acid-base equilibria Flashcards
What is degree of ionization?
quantity that dissociates/concentration before ionization
What is the relationship between Kw, Ka and Kb
Kw = Ka*Kb
What is a polyprotic acid?
An acid that can donate multiple protons
How does Ka change from 1st ionization to 2nd ionization?
Ka decreases
Under what conditions do only the first ionization affect pH?
When Ka differs 3 orders between ionizations
If the cation/anion of a salt is conjugate of a strong acid/base, what does that mean?
The cation/anion is neutral
If the cation of a salt is not conjugate of a strong acid/base, what does that mean?
The cation is acidic
If the anion of a salt is not conjugate of a strong acid/base, what does that mean?
If it has no ionizable H, it is basic. If it has an ionizable H, it is amphiprotic
What happens if the cation of a salt is acidic and the anion is basic?
The acidity is determined by which K is higher
What happens if the cation in a salt is acidic and the anion is neutral?
The salt will be acidic
What is the common ion effect?
When the equilibrium of an acid-base reaction is shifted by the addition of a salt with a common ion
What is a buffer and what is its purpose?
A solution containing an acid and its conjugate, to resist pH
What is the equation used to find the pH of buffers?
pH = pKa + log(HA/A)
What is a titrant and an analyte?
Analyte: solution of unknown concentration
Titrant: reactant added to analyte via buret
What is the equivalence point?
The point in a titration where titrant and analyte are present in stoichiometrically equal amounts
How do you find the pH in a titration reaction?
set up ICF table w/ initial moles, determine limiting reagant that will go to 0, determine x from limiting reagant. if the remaining reactant is strong, then [H] or [OH] will equal concentration of the acid. If the remaining acid is weak, must use Ka to find [H] or [OH]
