Chapter 16 Flashcards
(17 cards)
Buffer
A solution that will resist pH change. Usually a weak acid and its conjugate base
HH Equation
Can calculate the pH of a buffer solution when you have the initial concentrations
What else can buffers be made of?
A weak base and conjugate acid
Buffering limits
The buffering action is related to a stoichiometric consumption of either the weak acid or the conjugate base.
Buffer capacity
The amount of acid or base we can add to a buffer without destroying its effectiveness
pH range
The relative concentrations of acid and base should not differ by more than a factor of 10. It is finding the acid/base contractions from the pH and pk.
When is buffer capacity optimal?
When the ratio of acid and conjugate base buffer components does not differ by more than a factor of 10.
When is the buffer most effective
When the quantities of acid and base are significant
A buffer designed to be optimal and effective covers…
One unit above and one unit below the pKa
acid-base titration
involves reaction an unknown solution of a base (or acid) with a known solution of an acid (or base); at the equivalence point, the molar amounts of acid or base match.
What is the relationship between a strength strong acid and its conjugate base?
Because if a strong acid had a strong base then then it would undo the ionization reaction !
General properties of acids
sour, corrosive, reacts with basics to form ionic salts
Arrhenius definition
acid produces
protons H+ and a base produces hydroxide OH– in aqueous solution.
Brønsted–Lowry definitions
an acid is a
proton H+ donor and a base is a proton acceptor.
Strong Acids…
completely dissociate
The degree of dissociation of an acid
related to the attraction between
the proton and conjugate base.
When can water act as an acid
Autoionization
