Topic 4a- Acids and Bases Flashcards
Acidic Solutions: What is usually formed when we have H+ and H2O?
H3O+
What does an acid and base increase? which one is the acceptor and donor
Acid- H+, donor “add”
Base- OH-, Acceptor ‘take’
what is a acid and base together called?
amphiprotic
what happens when an acid dissolves in water?
-conjugate base are formed
-conjugate means “formed together”
-base to conj acid
-acid to conj base
explain how we could find the conj base for PH4+ and conj acid for HCO3-
base- seperate to H+ ion and watch the subtract exp (H+ + PH3)
acid- add the H and add exp (H2CO3) `
Strong acids will have _____ base
Strong Base will have ________ acid
partial weak will have
weak
-weak acid and weak bases
-bases are exceedingly strong
in any acid base reaction, the equilibrium will favour the reaction that moves the proton to the
stronger base
-helps determine A and B solution
what does a single arrow with a tiny reverse arrow mean
complete ionization
Ka (acid) formula
prod/ reac
-dont forget exp
larger Ka and larger Kb means
stronger the acid/base
what is autoionization
very few molecules acting as bases and acids
what does Kw refer too, whats its formula
ion product constant for water- look at temp on back of sheet
-always use 25 if kw not given
-can rearrange formula
Kw= [h30] [OH]
pH formula
pOH formula
pKw formula
pKa
- ” p” tells us to take negative logarithm
pH= -log [H3O+] also pKw- pOH=pH
pOH= -log [OH-]
pKw= - log kw also pH + pOH=pkw
pKa= - log Ka
name the seven strong acids
-HCl
-HBr
-HI
-HNO3
-H2SO4
-HClO3
-HClO4
if we have a strong acid, the concentration will be equal to
H+ concentration
name the 5 strong bases
-NaOH
-KOH
-Ca(OH)2
-Sr(OH)2
-Ba(OH)2
-watch for (OH)2 mols
how do you start out a concentration question for base, how does it differ to acid
-do pOH= pKw-pH
-pkw is usually 14
-then anti log
-acid does anti log right away
[A-] is also equal to
[H3O+]
Percent ionization formula
[H3O+] (also can Be A-)
__________________________. x 100
[HA] initial
what is the 400 rule
if [HA]/Ka is greater than 400, then your [HA] at equilibrium is the same number
-ignore x in the denominator
polyprotic acids have
more than on acid proton
more than one H+, (Ka1,Ka2,Ka3)
-each on gets smaller and smaller
-if the difference between ka1 and ka2 is 10x3 of more, pH depends only on first discossication
what is the rule for ka1 and ka2
if [HA]/Ka1 is greater than 400, then ignore ka2
Kb formula (base dissociation)
[HB] [OH-]
___________
[B-]
used to find the [OH-]
Ka formula (acid dissociation)
[H3O-] [A-]
____________
[HA]
-find H3O
Ka x Kb =
Kw
anions are acids or bases?
bases
-they from with water
cations are acids or bases?
-acids which will lower the pH
-greater charge will make cations more acidic
-metal cations will lower the pH too
6 things that effect cations and anions
- an anion that is the conjugate base of a strong acid will not affect the pH (Cl, NO3, CLO4 etc)
-an anion that is the conjugate base of a weak acid will increase the pH (F-, CH3COO)
-a cation that is a conjugate acid of a weak base will decrease the pH (NH4)
-cations of the strong arrhenius base will not affect the pH (Na, Li, K , Ca2+)
-other metal ions will decrease the pH (Al, Zn)
-When the solution contains both weak acid and weak base, the pH depends on Ka and Kb values
conjugate base meaning
remains after an acid donates (loses) a proton (H⁺)
A conjugate acid
he species that forms when a base accepts a proton
tips for determining acid, base, neutral from cations and anions
focus on concentration first: inc in concentration will dec the pH and vis versa
acidity increases what way on the table
inc from left to right
inc down the period
factors affecting acid strength
-electronegativity
- number of oxygens will inc the acid
-resonance struc of Carboxylic acid
-
what does lewis acids do
-electron pair acceptor
-has lewis base and lewis acid
-accepts lone pairs
whats a monoprotic acid? whats it equal too?
when it donates one H
for ka the h3o will be equal to
the other prod
Strong Acid and Base means
no ice
weak acid and base means
ice table
eg (0.30-x) what can we do
ignore the x
