Chem #10 Flashcards
what makes a stronger base
a stronger base has more EDG that would be able to stabilize a positive charge when a hydrogen is added
what does the Arrhenius definition of acids and bases refer to?
dissociation to form H+ or OH- ions
o Typically limited to aqueous acids and bases
o Very restrictive
Arrhenius acid
will dissociate to form an excess of H+ in solution
Have H at the beginning of their chemical name.
Arrhenius base
will dissociate to form an excess of OH- in solution
Have OH at the end of their chemical name.
what does the Bronsted-Lowry definition of acids and bases refer to?
donating or accepting H+
Bronsted-Lowry Acid
a species that donates H+
Bronsted-Lowry base
: a species that accepts H+
conjugate acid/base pairs
transfer of a proton from acid to base.
what does the Lewis definition of acids and bases refer to?
donating or accepting an electron pair
o Also known as coordinate covalent bond formation, complex ion formation, or nucleophile-electrophile interactions.
lewis acid
an electron pair acceptor
lewis base
electron pair donator
amphoteric species
one that reacs like an acid in a basic environment and like a base in an acidic environment.
o Amphiprotic: can gain or lose a proton.
o Ex: H2O and HSO4-
o Also species that can accept or donate electrons.
autoionization of water
water can react with itself.
For pure water at 298 K, the water dissociation constant Kw = 10-14
• Kw is only affected by temperature, not concentration, pressure, or volume changes.
lower pH is ___
acidic
higher pH is ___
basic
strong acids and bases
completely dissociate into their component ions in aqueous solutions.
o Contribution of ionization of water is only important if the concentration of the strong acid or base is near 10-7.
weak acids and bases
only partially dissociate in aqueous solutions, and the less it will dissociate.
acid dissociation constant
Acid dissociation constant, Ka
• The smaller the Ka, the weaker the acid.
base dissociation constant
Base dissociation constant, Kb
• The smaller the Kb, the weaker the base, and the less it will dissociate.
conjugate acid
the acid formed when a base gains a proton
conjugate base
the base formed when an acid loses a proton.
a strong acid has a ____ conjugate base
weak
EWG near an H on an acid _____ its acidic capabailities
increase
polyvalent
each mole of the acid or base liberates more than one acid or base equivalent.