LO 42 - 46 Flashcards
What is a neutralization reaction?
acids react with bases and produce H2O or sometimes a weak electrolyte
Weak acids do not _________ so they are notated by ↔ reaction arrows
fully ionize
________ acids contain more than one ionizable proton and release them _________
polyprotic
sequentially
_______ acids have one, first strongly ionizable proton and then a second weaker one
diprotic
________ acids contain only two elements
binary
How are binary acids named?
hydro + base name of nonmetal (-ic) + acid
________ contain H and an oxyanion which is a nonmetal + oxygen
oxyacid
How are oxyacids named when the oxyanion ends in -ate?
base name of oxyanion + -ic + acid
How are oxyacids named when the oxyanion ends in -ite?
base name of oxyanion + -ous + acid
Describe acid-base titrations
a substance in solution of known concentration is reacted with another solution of unknown concentration. an indicator such as dye is used to signal the equivalence point
What is the titration equivalence point
when the # of mols OH- equals the number of mols H+ in solution
Neutralization reactions between concentrated acids and bases are highly __________
exothermic
What are the 4 distinct characteristics of acids
- sour taste
- dissolve many metals
- turn litmas paper blue → red
- neutralize bases
What are the four distinct characteristics of bases
- bitter taste
- slippery feeling
- turn litmas paper red → blue
- neutralize acids
What is the Arrhenius definition of an acid
a substance that produces H+ ions in aqueous solution
What is the Arrhenius definition of a base
a substance that produces OH- ions in aqueous solution
Weakness or strength of an acid/base is determined by __________ according to Arrhenius
amount that dissociates into ions
What is the Bronsted-Lowry definition of an acid
a proton donor
What is the Bronsted-Lowry definition of a base
a proton acceptor
__________ substances such as H2O can act as an acid or a base
amphoteric
____________ acid-base pairs are two substances related to each other by the transfer of a proton
conjugate
Base + H+ → ______
conjugate acid
Acid - H+ → ________
conjugate base
What two factors affect the strength of a binary acid
- bond polarity
- bond strength
How does bond polarity impact the strength of a binary acid
Increasing the polarity of an “H-X” bond increases the strength of the acid. When shared electrons in an “H-X” bond spend most of their time close to “X” atom, the bond becomes polar. It also becomes weaker.
How does bond strength impact the strength of binary acids
the stronger the bond the weaker the acid because the H atom will be held more tightly
What two factors affect the strength of an oxyacid (HYOx)
- electronegativity of “Y”
- number of oxygens bonded to “Y”
How does the electronegativity of “Y” in an oxyacid (HYOx) impact strength of the acid
the more electronegative Y, the more it weakens and polarizes the H-O bond and thus the more acidic
How does the number of oxygens bonded to “Y” in an oxyacid (HYOx) impact strength of the acid
additional O atoms are electronegative and thus draw e- density away from the bonds to Y and H, weaking the bonds and increasing acidity
The ______ ________ constant (Ka) quantifies the relative strength of a weak acid based on the law of mass action
acid ionization
The smaller Ka is, the _______ the acid ionizes thus indicating it as _______
less
weaker
Because water is amphoteric, it acts as an acid or base with itself in a process known as ________
autoionization
The ______________ of water (Kw) represents H2O at equilibrium
ion product constant
Kw = ____________ (concentration terms) @ 25°C
[H3O+] · [OH-]
Kw = ____________ (numeric) @ 25°C
1.0 · 10^-14
A neutral solution contains
[H3O+] = [OH-] = ____________ @ 25°C
1.0 · 10^-14
An acidic solution contains
[H3O+] _____ [OH-]
>
A basic solution contains
[H3O+] _____ [OH-]
<
In aqueous solutions both [H3O+] and [OH-] are present and _________ holds true
[H3O+] · [OH-] = 1.0 · 10^-14
A “p” scale of any kind indicates the _________ of a value
-log (x)
The pH scale specifics the _______ of a solution as given by pH = _______
acidity
-log [H3O+]
pH + pOH = ______
14
The numbers to the right of the decimal place in a pH or pOH value correspond to the number of ________________
significant figures in the negative log
ex. -log (1.0 · 10^-3) = 3.00 pH
2 sig figs 2 decimal places
pKa = _________ where the smaller the pKa value, the _________ the associated acid
-log(Ka)
stronger
For oxyacids (H-X-O):
more electronegative X = _________
more O atoms = ___________
stronger,
stronger
For binary acids (H-A):
larger the atom = ____________
stronger
Strong acids and strong bases do not ____________________. As such, when you get the conjugates of a SA or SB in the products side of a reaction . . .
reform in solution
they will be neutral
