Acid base buffers Flashcards
(19 cards)
what is a Brønsted–Lowry acid
a proton donor
what is a Brønsted–Lowry base
a proton acceptor
what is a strong acid or base
an acid or base that almost completely ionises in water
what is a weak acid or base
an acid or base that only slightly ionises in water
what do acid base reactions involve
the transfer of protons
what is a monoprotic acid
an acid that releases one hydrogen ion per molecule of acid
what is a diprotic acid
an acid that releases two hydrogen ions per molecule of acid
what is water in terms of acid-base
water is amphoteric it can act as both a base and as an alkali
what is the equivalence point
the point in a titration at which the reaction is just complete
what is the end point
the volume of acid or alkali added
when the indicator changes colour
What is the affect of adding an acid to an acidic buffer
Equilibrium shifts to the left
H+ ions react with A- to form more HA
What is the effect of adding a base to an acidic buffer
Equilibrium shifts to the right
OH- ions react with H+ ions removing them from solution
So more acid dissociates
what is Kw
the ionic product of water
why is pure water always neutral
the concentration of hydrogen ions and hydroxide ions are equal
what is a buffer
a solution that resists changes in pH when small amounts of acid or alkali are added
what is an acidic buffer
pH less than 7
contain a mixture of weak acid with one it’s salts
resist pH when acid or base is added
what is a basic buffer
pH greater than 7
contain a mixture of a weak base with one of it’s salts
resist pH when acid or base is added
what is the effect of adding an acid to a basic buffer
equlibrium moves to the right
to replace the OH- ions removed
as H+ ions react with OH- ions
what is the effect of adding a base to a basic buffer
equlibrium moves to the left
as OH- ions react with salt to form base
so equlibrium shifts to remove OH- ions
