According to Bronsted-Lowry, _____ is a proton donor and _____ is a proton acceptor.
acid
base
17.1.2
HCl is a(n) _____. Its conjugate _____ is...
acid
base
Cl-
17.1.6
H2O(l)+NH3(aq) ->^2 OH-(aq)+NH4+(aq)
acid donor
base acceptor
conj. base
conj. acid
17.1.3
____ ____ occurs when ions produced by the dissociation of a salt react with water to produce ____ or ____.
salt hydrolysis
hydroxide ion
hydronium ion
17.2.31
Calculate the pH of a 0.074 M solution of HF. Ka for HF is
6.5*10^-4
pH=2.16
review sheet 2, question 2
Kb= ?/?
___= Ka*?
Ka= ?/?
Kb= (Kw)/(Ka)
Kw= Ka*Kb
Ka= (Kw)/(Kb)
17.2.42-43
HCl
hydrochloric acid
17.1.10
A _____ _____ ionizes completely in water. It is present entirely as ions; it is a _____ electrolyte.
example:HCl
strong acid
strong
17.1.10
HNO3 is a(n) _____. Its conjugate _____ is...
acid
base
NO3-
17.1.6
CH3COO-(aq)+H2O(l) ->^2 OH-(aq)+CH3COOH(aq)
base acceptor
acid donor
conj. base
conj. acid
17.1.3
Consider the solution of sodium cyanide, NaCN.
NaCN(s) -> Na+(aq)+CN-(aq)
A 0.1 M solution NaCN has a pH of 11.1 and is therefore fairly basic. How is this possible?
salt hydrolysis
17.2.30
Aniline, C6H5NH2, is used in the manufacture of some perfumes. What is the pH of a 0.200 M solution of aniline at 25^oC ?
Kb= 4.2*10^-10 at 25^oC .
pH= 8.96
17.2.29
____ is called the base ionization constant.
Kb
17.2.24
HI
hydroiodic acid
17.1.10
A ____ ____ is a substance that can accept a pair of electrons whereas a ____ ____ is a substance that can donate a pair of electrons.
lewis acid
lewis base
17.2.53
SO42- is a(n) _____. Its conjugate _____ is...
base
acid
HSO4-
17.1.6
What does the word proton refer to in the context of conjugate acids and bases?
it refers to H+
17.1.8
Predict whether a 0.10-M solution of each of the following salts will be basic, acidic, or neutral:
a. KClO4
b. (CH3)3NHCl
c. K2C2O4
d. CH3NH3NO3
e. NaHCO3
a. neutral, neither K+ nor ClO4- hydrolyze
b. acidic, (CH3)3NH+ hydrolyzes
c. basic, C2O42- hydrolyzes
d. acidic, CH3NH3+ hydrolyzes
e. basic, HCO3- hydrolyzes
17.2.38
Nitrous acid (HNO2) is a weak acid with a Ka of 4.5*10^-4 . Sodium nitrite (NaNO2) is therefore a strong base. What will be the pH of a solution of 0.065 M sodium nitrite?
pH=8.08
review sheet 2, question 4
A weak monoprotic acid is 0.50% ionized in a 1.0 M solution. Calculate the ionization constant of the acid.
Ka= 2.5*10^-5
17.2.16
HBr
hydrobromic acid
17.1.10
A _____ _____ ionizes completely in water. It is present entirely as ions; it is a _____ electrolyte.
example: LiOH,NaOH,KOH
strong base
strong
17.1.11
H3PO4 is a(n) _____. Its conjugate _____ is...
acid
base
H2PO4-
17.1.6
a. the conjugate base of H2O...
b. the conjugate acid of O2-...
c. the conjugate acid of HCO3-...
d. the conjugate base of HSO4-...
a. OH-
b. OH-
c. H2CO3
d. SO42-
17.1.8
Will it hydrolyze?
HNO3
HCN
OH-
NH3
no
yes
no
yes
17.2.33
Calculate the pH at the titration endpoint, when 35.00 mL of 0.200 M methyl amine (CH3NH2) is titrated by 0.120 M hydrochloric acid. (Kb CH3NH2= 4.4*10^-4 )
pH = 5.85
review sheet 2, problem 6
A 0.015 M solution of a weak acid has a pH of 4.27. What is the Ka for this acid?
Ka= 1.92*10^-7
review sheet 2, question 1
HNO3
nitric acid
17.1.10
A _____ _____ ionizes partly in water. It is present primarily as molecules and partly as ions; it is a _____ electrolyte.
weak acid
weak
17.1.10
NH3 is a(n) _____. Its conjugate _____ is...
base
acid
NH4+
17.1.6
To find a conjugate base of a species, ____ a proton from the formula.
TO find the conjugate acid of a species, ____ a proton to the formula.
remove
add
17.1.8
Predict whether a 0.10 M solution of KNO2 will be basic, acidic, or neutral and why?
Ions in solution: K+ and NO2-
K+ is a Group 1A cation, and KOH is a strong base. NO2- is the conjugate base of the weak acid HNO2.
The anion hydrolyzes, thus making the solution BASIC.
17.2.36
Oxalic acid (H2C2O4) is a diprotic acid with Ka1= 5.9*10^-2 and Ka2= 6.4*10^-5 .What is the pH of the solution of 0.035 M oxalic acid? (can one neglect the second ionization?)
pH=1.61
review sheet 2, question 3
Determine the Kb of the acetate ion (C2H3O2-). The Ka of acetic acid (HC2H3O2) is 1.8*10^-5 .
Kb= 5.6*10^-10
17.2.44
H2SO4
sulfuric acid
17.1.10
The larger the value of ____, the ____ the acid.
Ka
stronger
17.2.3
C6H5O73- is a(n) _____. Its conjugate _____ is...
base
acid
HC6H5O72-
17.1.6
Predict Products:
PO43-(aq)+H2O(l) -> ?
PO43- is a base because it accepts a proton. (HPO42-) = conjugate acid
H2O is an acid because it donates a proton. (OH-) = conjugate base
PO43-(aq)+H2O(l) -> HPO42-(aq)+OH-(aq)
17.1.9
Predict whether a 0.10 M solution of each salt will be basic, acidic, or neutral and why?
a. LiI
b. NH4NO3
a. Ions in solution: Li+ and I-
Li+ is a group 1A cation and LiOH is a strong base. I- is the conjugate base of the strong acid HI. Therefore the solution is neutral because neither hydrolyze.
b. Ions in solution: NH4+ and NO3-
NH4+ is the conjugate acid of the weak base NH3. NO3- is the conjugate base of the strong acid HNO3. Therefore the solution is acidic because the cation will hydrolyze.
17.2.35
You are given 275 mL of a buffer which is 0.25 M in acetic acid and 0.15 M in sodium acetate. To this buffer you add 55 mL of 0.30 M sodium hydroxide. Calculate the pH of the buffer before and after the addition of the sodium hydroxide.
before: pH = 4.52
after: pH = 4.79
review sheet 2, question 5
Aspirin (acetylsalicylic acid, HC9H7O4) is a weak acid. It ionizes in water according to the equation: HC9H7O4(aq)+H2O(l) ->^2 H3O+(aq)+C9H7O4-(aq). A 0.10 M aqueous solution of aspirin has a pH of 2.27 at 25^oC . Determine the Ka of aspirin.
3.0*10^-4
17.2.15
HClO3
chloric acid
17.1.10
A _____ _____ ionizes partly in water. It is present primarily as molecules and partly as ions; it is a _____ electrolyte. These are nitrogenous ____ such as NH3.
weak base
weak
bases
17.1.11
H2O is a(n) _____. Its conjugate _____ is...
acid and base
base, OH-
acid, H3O+
17.1.6
Predict Products:
H2PO4-(aq)+CN-(aq) -> ?
H2PO4- donates an electron, therefore is an acid. (HPO42-) = conjugate base
CN- accepts an electron, making it a base. (HCN) = conjugate acid
H2PO4-(aq)+CN-(aq) -> HPO42-(aq)+HCN(aq)
17.1.9
Write the hydrolysis reactions and K expressions for:
a. (CH3)3NH+
b. C2O42-
c. CH3NH3+
d. HCO3-
a. (CH3)3NH++ H2O ->^2 (CH3)3N+H3O+
Ka=[(CH3)3N][H3O+]/[(CH3)3NH+]
b. C2O42-+H2O ->^2 HC2O4-+OH-
Ka=[HC2O4-][OH-]/[C2O42-]
c. CH3NH3++H2O ->^2 CH3NH2+H3O+
Ka=[CH3NH2][H3O+]/[CH3NH3+]
d. HCO3-+H2O ->^2 H2CO3+OH-
Ka=[H2CO3][OH-]/[HCO3-]
17.2.40
What is the pH of a 0.040 M ammonia solution at 25^oC. Kb= 1.8*10^-5.
pH=10.93
17.2.28
Determine the Ka of the methyl ammonium ion (CH3NH3+)
Kb of methyl amine (CH3NH2) is 4.4*10^-4 .
Ka= 2.3*10^-11
17.2.45
HClO4
perchloric acid
17.1.10