Acids/bases mc problems
Determine each of the following for a 0.800M HBr solution: pH
.097
A 10.0mL sample of vinegar, which is an aqueous solution of acetic acid, HC2H3O2, requires 19.5mL of 0.350M NaOH to reach the endpoint in a titration. HC2H3O2(aq) + NaOH(aq) → NaC2H3O2(aq) + H2O(l) What is the molarity of the acetic acid solution?
.683M
A water solution has the pH = 10.00, Determine the molar concentration of H3O+ in this solution.
1.0×10−10 M
Determine the molar concentration of OH− in this solution.
1.0×10−4 M
Consider a neutral water solution, determine the molar concentration of H3O+ in this solution.
1.0×10−7 M
Determine the molar concentration of OH− in this solution.
1.0×10−7 M
Find pH: [H3O+] = 3.0×10−2M
1.52
Consider a water solution with molar concentration of H3O+ =6.4×10−12. Determine the molar concentration of OH− in this solution.
1.6×10−3 M
Calculate the pH of this buffer if it is 0.55M H3PO4 and 0.21M H2PO4−. The Ka for H3PO4 is 7.5×10−3.
1.71
Find pH: [OH−] = 4.5×10−4M
10.65
Calculate the pH: [OH−] = 7.7×10−4M
10.89
Calculate the pH of ammonia, which has an [H3O+] = 1.0×10−11 M
11
Determine the pH of this solution.
11.2
Find pH: [OH−] = 5.5×10−3M
11.74
What is the pH of a solution prepared by dissolving 5.00g Ca(OH)2 in water to make 805mL of solution?
13.22
Determine the molar concentration of OH− in this solution.
2.0×10−3 M
A buffer is made by dissolving H3PO4 and NaH2PO4 in water. Calculate the pH of this buffer if it is 0.10M H3PO4 and 0.10M H2PO4−. The Ka for H3PO4 is 7.5×10−3
2.12
Find pH: [H3O+] = 4.4×10−3M
2.36
Predict the products and write the balanced equation for the reaction of HNO3 with each of the following metals. Al
2Al(s)+6HNO3(aq)→2Al(NO3)3(aq)+3H2(g)
Balance HNO3(aq)+Ba(OH)2(s)→Ba(NO3)2(aq)+H2O(l)
2HNO3(aq)+Ba(OH)2(s)→Ba(NO3)2(aq)+2H2O(l)
Predict product and balance HNO3(aq) and Ca(OH)2(s)→
2HNO3(aq)+Ca(OH)2(s)→Ca(NO3)2(aq)+2H2O(l)
Calculate the pH: [H3O+] = 1.0×10−3M
3
Calculate the pH: [OH−] = 4.0×10−11M
3.6
Balance H2SO4(aq)+Al(OH)3(s)→Al2(SO4)3(aq)+H2O(l)
3H2SO4(aq)+2Al(OH)3(s)→Al2(SO4)3(aq)+6H2O(l)
Find pH: [H3O+] = 1×10−4M
4
Consider a water solution with pH = 11.3, determine the molar concentration of H3O+ in this solution.
5.00×10−12 M
Find pH: [OH−] = 8.0×10−9M
5.9
How many milliliters of a 0.205M NaOH solution are needed to completely neutralize 6.00mL of a 0.930M H2SO4 solution? H2SO4(aq)+2NaOH(aq)→Na2SO4(aq)+2H2O(l)
54.4mL
Determine the pH of this solution.
7
Calculate the pH: [H3O+] = 6.6×10−8M
7.18
Find pH: [OH−] = 1.9×10−7M
7.28
Find pH: [H3O+] = 1.5×10−8M
7.82
Calculate the pH: [H3O+] = 6.0×10−9M
8.22
Calculate the pH: [OH−] = 2.0×10−5M
9.3
What is meant by the phrase "A weak acid has a strong conjugate base"?
A weak acid dissociates only slightly, therefore its conjugate base has a strong attraction for protons.
Is this solution acidic, basic, or neutral?
Acidic
acidic, basic, or neutral solution: [H3O+]=1.3×10−4M
Acidic
acidic, basic, or neutral solution: [OH−]=4.0×10−12M
Acidic
acidic, basic, or neutral: cheese, pH 5.2
Acidic
acidic, basic, or neutral: coffee, pH 5.54
Acidic
acidic, basic, or neutral: honey, pH 3.9
Acidic
acidic, basic, or neutral: rain, pH 5.83
Acidic
acidic, basic, or neutral: shampoo, pH 5.7
Acidic
acidic, basic, or neutral: soda, pH 3.22
Acidic
acidic, basic, or neutral: tomatoes, pH 4.2
Acidic
Is this solution acidic, basic or neutral?
Basic
Is this solution acidic, basic, or neutral?
Basic
acidic, basic or neutral?
Basic
acidic, basic, or neutral solution: [H3O+]=7.0×10−12M
Basic
acidic, basic, or neutral solution: [OH−]=1.5×10−2M
Basic
acidic, basic, or neutral: blood, pH 7.38
Basic
acidic, basic, or neutral: chocolate cake, pH 7.6
Basic
acidic, basic, or neutral: drain cleaner, pH 11.2
Basic
acidic, basic, or neutral: laundry detergent, pH 9.4
Basic
neutral, basic or acidic?
Basic
Write the conjugate base for HC2H3O2.
C2H3O2−
which is the stronger base? (table 10.3) H2O or CN−
CN-
Write the formula of the conjugate base for acid HCN
CN−
Write the formula of the conjugate base for HCO−3.
CO32−
which is the stronger base? (table 10.3) CO32− or H2O
CO32−
calcium hydroxide
Ca(OH)2
Predict the products and write the balanced equation for the reaction of HNO3 with each of the following metals. CA
Ca(s)+2HNO3(aq)→Ca(NO3)2(aq)+H2(g)
Predict the products and write the balanced equation for the reaction of H2SO4 with each of the following carbonates or hydrogen carbonates. CaCO3
CaCO3(s)+H2SO4(aq)→CaSO4(s)+CO2(g)+H2O(l)
T/F A weak acid has a weak conjugate base.
F
T/F A weak acid is completely ionized in aqueous solution.
F
which is the stronger base?(table 10.3) H2PO4− or F−
F-
iron(III) hydroxide
Fe(OH)3
H2O or H2CO3 which is a stronger acid? Table 10.3
H2CO3
HF or H2CO3 Which is a weaker acid?
H2CO3
Write the conjugate acid for HCO3−.
H2CO3
Carbonic acid, a weak acid, reacts with water to form bicarbonate and hydronium ion. Write the equation for the dissociation of carbonic acid.
H2CO3(aq)+H2O(l)⇌HCO3−(aq)+H3O+(aq)
HSO4− or H2O Which is a weaker acid?
H2O
Write the formula of the conjugate acid for base OH−.
H2O
Write the formula of the conjugate base for acid H3O+
H2O
A buffer is made by dissolving H3PO4 and NaH2PO4 in water. Write an equation that shows how this buffer neutralizes added acid.
H2PO4−(aq)+H3O+(aq)→H3PO4(aq)+H2O(l)
Predict the products and write the balanced equation for the reaction of H2SO4 with each of the following carbonates or hydrogen carbonates. CsHCO3
H2SO4(aq)+2CsHCO3(aq)→2H2O(l)+2CO2(g)+Cs2SO4(aq)
Write the neutralization equation for NaOH and H2SO4.
H2SO4(aq)+2NaOH(aq)→Na2SO4(aq)+2H2O(l)
Predict the products and write the balanced equation for the reaction of H2SO4 with each of the following carbonates or hydrogen carbonates. Na2CO3
H2SO4(aq)+Na2CO3(aq)→CO2(g)+H2O(l)+Na2SO4(aq)
phosphoric acid
H3PO4
Balance H3PO4(aq)+KOH(aq)→K3PO4(aq)+H2O(l)
H3PO4(aq)+3KOH(aq)→K3PO4(aq)+3H2O(l)
Predict products and balance H3PO4(aq) and NaOH(aq)→
H3PO4(aq)+3NaOH(aq)→Na3PO4(aq)+3H2O(l)
A buffer is made by dissolving H3PO4 and NaH2PO4 in water. Write an equation that shows how this buffer neutralizes added base.
H3PO4(aq)+OH−(aq)→H2PO4−(aq)+H2O(l)
Determine each of the following for a 0.800M HBr solution: the balanced equation when reacted with LiOH
HBr(aq)+LiOH(aq)→LiBr(aq)+H2O(l)
Which acid has the weaker conjugate base? HPO42− HCHO2
HCHO2
Which acid produces more ions?
HCHO2
HCl or HF which is a stronger acid? Table 10.3
HCl
Predict products and balance HI(aq) and LiOH(aq)→
HI(aq)+LiOH(aq)→LiI(aq)+H2O(l)
Which is the stronger acid?
HNO2
Write the formula of the conjugate acid for base NO2−
HNO2
nitrous acid
HNO2
HBr or HNO3 Which is a weaker acid?
HNO3
Write the formula of the conjugate acid for base NO3−
HNO3
HPO42−(aq) + H2O(l) ⇌H3O+(aq) + PO43−(aq) Ka=2.2×10−13 HCHO2(aq)+H2O(l)⇌H3O+(aq) +HCO2−(aq) Ka=1.8×10−4 Which is the weaker acid, HPO42− or HCHO2?
HPO42−
Write the formula of the conjugate acid for base SO42−
HSO4−
NH+4 or HSO−4 which is a stronger acid? Table 10.3
HSO−4
What is the Ka expression for HCO−3?
Ka=[H3O+][CO32−]/[HCO3−]
Identify the correct equilibrium expression for its acid dissociation constant.
Ka=[H3O+][HCO3−][H2CO3]
What is the value of Kw?
Kw = 1.00×10−14M×M
What is the meaning of Kw?
Kw is the product of the concentrations of the H3O+ and OH− in water
Consider the buffer system of nitrous acid, HNO2, and its salt, NaNO2. HNO2(aq)+H2O(l) ←−→ H3O+(aq)+NO−2(aq) The purpose of the buffer system is to:
Maintain pH
A solution of 0.154M NaOH is used to neutralize 21.0mL H2SO4 solution. H2SO4(aq) + 2NaOH(aq) → Na2SO4(aq) + 2H2O(l) If 34.4mL NaOH solution is required to reach the endpoint, what is the molarity of the H2SO4 solution?
Molarity = .126 M
A solution of 0.314M KOH is used to neutralize 13.0mL H3PO4 solution. H3PO4(aq) + 3KOH(aq) → K3PO4(aq) + 3H2O(l) If 28.3mL KOH solution is required to reach the endpoint, what is the molarity of the H3PO4 solution?
Molarity = .228 M
If 29.7mL of 0.245M KOH is required to completely neutralize 21.0mL of a HC2H3O2 solution, what is the molarity of the acetic acid solution? HC2H3O2(aq) + KOH(aq) → KC2H3O2(aq) + H2O(l)
Molarity = .347 M
Write the formula of the conjugate base for acid NH4+
NH3
Write the conjugate acid for NH3.
NH4+
which is the stronger base? (table 10.3) SO42− or NO2−
NO2-
Write the formula of the conjugate base for HNO2.
NO2−
sodium hydroxide
NaOH
What is the conjugate base of HPO42−?
PO43−
Write the formula of the conjugate base for acid HPO42−
PO43−
Write the conjugate base for HS−.
S2-
T/F A weak acid has a small value of Ka.
T
T/F A weak acid has a strong conjugate base.
T
T/F A weak acid is slightly ionized in aqueous solution.
T
Using Table 10.3 in the textbook, predict whether each of the following reactions contains mostly reactants or products at equilibrium. H3PO4(aq)+F−(aq)⇌HF(aq)+H2PO4−(aq)
The products are favored.
CO32−(aq) + H2O(l) ⇌OH−(aq)+HCO3−(aq)
The reactants are favored.
HS-(aq) + H2O(l) ⇌H3O+(aq)+S2−(aq)
The reactants are favored.
Determine each of the following for a 0.800M HBr solution: milliliters of HBr solution required to neutralize 12.0mL of a 0.950M LiOH solution
VHBr = 14.3mL
Predict the products and write the balanced equation for the reaction of HNO3 with each of the following metals. Zn
Zn(s)+2HNO3(aq)→Zn(NO3)2(aq)+H2(g)
Determine each of the following for a 0.800M HBr solution: [H3O+]
[H3O+] = 0.800M
Calculate the [H3O+] of each aqueous solution with the following [OH−]. dishwashing detergent, 1.0×10−3M
[H3O+] = 1.0×10−11M
What is the values of [H3O+] for a solution with [OH−] = 7×10 −6 M?
[H3O+] = 1×10−9M
Calculate the [H3O+] of each aqueous solution with the following [OH−]. seawater, 2.2×10−6M
[H3O+] = 4.5×10−9M
What are the [H3O+] and [OH−] for a solution with each of the following pH values? pH1 = 10.5
[H3O+] =3×10−11M [OH−] =3×10−4M
Calculate the [H3O+] of each aqueous solution with the following [OH−]. aspirin, 1.9×10−11M
[H3O+] =5.3×10−4M
Calculate the [H3O+] of each aqueous solution with the following [OH−]. milk of magnesia, 1.1×10−5M
[H3O+] =9.1×10−10M
What is the Ka expression for HNO2?
[H3O+]/[HNO2][NO2−]
In a basic solution, how does the concentration of H3O+ compare to the concentration of OH−?
[H3O+]<[OH−]
What are the values of [H3O+] and [OH−] for a solution with pH = 4.25?
[H3O+]= 5.6×10−5M [OH−] = 1.8×10−10M
What are the [H3O+] and [OH−] for a solution with each of the following pH values? pH5 = 1.80
[H3O+]=1.6×10−2M [OH−] = 6.3×10−13M
What are the [H3O+] and [OH−] for a solution with each of the following pH values? pH3 = 6.80
[H3O+]=1.6×10−7M [OH−] = 6.3×10−8M
What are the [H3O+] and [OH−] for a solution with each of the following pH values? pH2 = 5.2
[H3O+]=6×10−6M [OH−] = 2×10−9M
What are the values of [H3O+] and [OH−] for a solution with pH = 2.04?
[H3O+]=9.1×10−3 M [OH−] = 1.1×10−12M
Calculate the [OH−] of each aqueous solution with the following [H3O+]. baking soda, 2.0×10−8M
[OH−] = 5.0×10−7M
What is the value of [OH−] for a solution with [H3O+] = 6.4 × 10−5M?
[OH−] =1.6×10−10M
Calculate the [OH−] of each aqueous solution with the following [H3O+]. bleach, 6.0×10−12M
[OH−] =1.7×10−3M
Calculate the [OH−] of each aqueous solution with the following [H3O+]. milk, 3.5×10−7M
[OH−] =2.9×10−8M
Calculate the [OH−] of each aqueous solution with the following [H3O+]. orange juice, 2.0×10−4M
[OH−] =5.0×10−11M
acid, base, or both: turns litmus red
acid
Identify the reactant that is a Brønsted-Lowry acid and the reactant that is a Brønsted-Lowry base in CO32−(aq)+H2O(l)←−→HCO3−(aq)+OH−(aq)
acid (proton donor) H2O, base (proton acceptor) CO2−3
Identify the reactant that is a Brønsted-Lowry acid and the reactant that is a Brønsted-Lowry base in NH3(aq)+H2O(l)←−→NH4+(aq)+OH−(aq)
acid (proton donor) H2O, base (proton acceptor) NH3
Identify the acid and base on the left side of the following equations and identify their conjugate species on the right side. CO32−(aq)+H2O(l)←−→OH−(aq)+HCO3−(aq)
acid H2O and base CO32−; conjugate base OH− and conjugate acid HCO3−
acidic, basic, or neutral: vinegar, pH 2.8
acidic
Name Al(OH)3
aluminum hydroxide
Write the name of NH4+
ammonia
acid, base, or both: has a slippery feel
base
acid, base, or both: neutralizes acids
base
acid, base, or both: produces OH− ions in water
base
Identify the acid and base on the left side of the following equations and identify their conjugate species on the right side. CH3NH2(aq)+H2O(l)←−→CH3NH3+(aq)+OH−(aq)
base CH3NH2 and acid H2O; conjugate acid CH3NH3+ and conjugate base OH−
Identify the acid and base on the left side of the following equations and identify their conjugate species on the right side. HBr(aq)+H2O(l)→H3O+(aq)+Br−(aq)
base H2O and acid HBr; conjugate acid H3O+ and conjugate base Br
acid, base, or both: conducts an electrical current
both
Name HClO3
chloric acid
Write the name of CN−
cyanide ion
Name HBr
hydrobromic acid
Write the name of HSO4−
hydrogen sulfate ion
In a buffer system: The weak acid is needed to:
neutralize added OH- provide the conjugate acid
Write the name for HNO3
nitric acid
Name HNO2
nitrous acid
write the name for HNO2
nitrous acid
Calculate the pH: [H3O+] = 5.6×10−2M
pH = 1.25
Calculate the pH: [OH−] = 8.1×10−4M
pH = 10.91
Calculate the pH: [OH−] = 5.0×10−3M
pH = 11.70
Calculate the pH: [OH−] = 8.0×10−2M
pH = 12.90
What is pH for a solution with [H3O+] =6.4×10−5M?
pH = 4.19
Acetic acid has a Ka of 1.8×10−5. What is the pH of a buffer solution containing 0.11M HC2H3O2 (acetic acid) and 0.20M C2H3O2−?
pH = 5
Calculate the pH: [H3O+] = 8.0×10−6M
pH = 5.10
What is pH for a solution with [OH−] = 7×10−6M?
pH = 8.8
Calculate the pH: [H3O+] = 6.0×10−8M
pH =7.22
Compare the pH of an H2CO3 buffer (the first buffer) that contains 0.10M H2CO3 and 0.10M NaHCO3 with another H2CO3 buffer (the second buffer) that contains 0.15M H2CO3 and 0.050M NaHCO3. Carbonic acid has a Ka of 4.3×10−7.
pH of the first buffer is greater than pH of the second buffer
Write the name of PO43−
phosphate ion
Name KOH
potassium hydroxide
Consider the buffer system of nitrous acid, HNO2, and its salt, NaNO2. HNO2(aq)+H2O(l) ←−→ H3O+(aq)+NO−2(aq) When OH− is added, the equilibrium shifts in the direction of the:
products
Name H2SO4
sulfuric acid
The addition of H3O+ is neutralized by:
the salt
Write the name of H2O
water
write the name for H2O
water
