Assignment 9: Acids and Bases Flashcards
arrhenius acid
a substance that when added to water gives/produces H+ ion(s)
- increases [H+] in an aqueous solution
arrhenius base
a substance that when added to water gives/produces OH- ion(s)
- increases [OH-] in an aqueous solution
definition
strong acid/base
a substance that dissociates completely (all HCl turns into H+ and Cl-)
definition
weak acid/base
a substance that doesn’t dissociate completely (there is a reverse reacton at equilibrium, so the ions are turned back into an acid/base)
keq for water = kw
kw = [H+][OH-] = 10-14
kw = (ka)(kb)
pH
-log[H+]
pOH
-log[OH-]
pkw
= -logkw
= -log([H+][OH-]} = -log[H+] + -log[OH-]
= pH + pOH
= 14
examples
strong acid
HCl, H2SO4, HNO3
Brønsted-Lowry Definition
acid: gives a proton (H+)
base: accepts/receives/takes a proton (H+)
neutralization reaction
reaction between an acid and a base
examples
strong bases
IA, KOH, NaOH
examples
weak acids
HAc(HC2H3O2), NH4+
examples
weak bases
NH3, Ac-
buffer
a combination of a weak acid and it’s conjugate base in roughly equal proportions, so that any added strong acid or base can be neutralized by the available weak acid or base without the pH changing very much ([H+] is very close to Ka)
ksp = [A][B]
equilibrium
ksp < [A][B]
precipitate forms
ksp > [A][B]
no precipitate forms (just ions)
ksp
= [prod]
- the keq of a saturated solution at equilibrium where the reactants are solids
saturated solution
solution with maxium amount of solute, such that if any more solute was added, it wouldn’t dissolve
conjugate acid/base pair
a pair of an acid and a base that differ only by an H+ and OH-
relative strength/size of conjugate acid/base pairs
strong/very large acid —> very weak/very small base
weak/large acid —> weak/small base
weak/small acid —> weak/large base
very weak/very small —> strong/very large base
[H+] = ka
pH = pka
[HIn] = [In-]
mixed color
[H+] > ka
pH < pka
[HIn] > [In-]
color of acid (HIn)
(if [HIn]:[In-] is 10:1, then pH = pka - 1)
[H+] < ka
pH > pka
[HIn] < [In-]
color of base (In-)
(if [HIn]:[In-] is 1:10, then pH = pka + 1)
equilibrium
ksp = [A][B]
precipitate forms
ksp < [A][B]
no precipitate forms (just ions)
ksp > [A][B]
NH4+1
ammonium
OH-1
hydroxide
CO3-2
carbonate
PO4-3
phosphate
SO4-2
sulfate
NO3-1
nitrate
C2H3O2-1
acetate
ammonium
NH4+1
hydroxide
OH-1
carbonate
CO3-2
phosphate
PO4-3
sulfate
SO4-2
nitrate
NO3-1
acetate
C2H3O2-1