Deck 14: Acids, Bases and Salts

Question 1

Which of the following statements about acids and bases is incorrect?

A) All Arrhenius acids are Bronsted-Lowry acids.
B) Arrhenius acid-base definitions are based on water as the solvent.
C) All Bronsted-Lowry bases are Arrhenius bases.
D) Bronsted-Lowry acid-base definitions are independent of solvent identity.

Answer 1

All Bronsted-Lowry bases are Arrhenius bases.

Question 2

In an Arrhenius acid-base context, the compounds KOH, H₂SO₄, and HNO₃ when dissolved in water, function respectively as a(n) ________.

A) base, acid and acid
B) acid, base and base
C) base, acid and base
D) base, base and acid

Answer 2

base, acid and acid

Question 3

Which of the following is incorrectly classified as an acid, a base, a salt, or an amphoteric species?

A) HCO₃^- amphoteric
B) NH₃ base
C) KF salt
D) S^2- amphoteric

Answer 3

S^2- amphoteric

Question 4

Which of the following is incorrectly classified as an acid, a base, a salt, or an amphoteric species?

A) H₂S acid
B) NH₄⁺ base
C) LiOH base
D) HS^- amphoteric

Question 5

Each of the following can act like a Bronsted-Lowry acid and Bronsted-Lowry base except:

A) NH₄⁺
B) H₂PO₄^-
C) HCO₃^-
D) HS^-

Question 6

The hydrogen sulfate ion HSO₄^- is amphoteric. In which of the following equations does it act as an acid?

A) HSO₄^- + H₂O $\rightarrow$ H₂SO₄ + OH^-
B) HSO₄^- + H₃O⁺ $\rightarrow$ SO₃ + 2H₂O
C) HSO₄^- + H₂O $\rightarrow$ SO₄^-2 + H₃O⁺
D) HSO₄^- + OH^- $\rightarrow$ H₂SO₄ + O^-2

Question 7

Which of the following could not be a Bronsted-Lowry acid?

A) HF
B) HC₂H₃O
C) CN^-
D) HS^-

Question 8

The Bronsted-Lowry acid and base for the reaction
NH₄⁺ + CN $\rightarrow$ NH₃ + HCN are, respectively, ________.

A) NH₃ and CN^-
B) NH₄⁺ and HCN
C) CN^- and HCN
D) NH₄⁺ and CN^-

Question 9

Which of the following is not a conjugate acid/base pair?

A) PH₄⁺/PH₃
B) H₂O/OH^-
C) HSO₄^-/SO₄^2-
D) S^2-/H₂S

Question 10

In the reaction below, identify the conjugate acid-base pair. (The acid is listed first in the pair.)
H₂PO₄^? + S^2- $\rightarrow$ HS^- + HPO₄^2-

A) S^-2   HS^-
B) H₂PO₄^-   S^-2
C) H₂PO₄^-   HPO₄^-2
D) HS^-   H₂PO₄^-

Question 11

Which of the following pairs of acids and conjugate bases is incorrectly labeled?

A) HSO₄^-     SO₄^-2
B) HFO₂     HFO₃
C) HSO₃^-     SO₃^-2
D) NH₄⁺ NH₃

Question 12

In which of the following pairs of acids are both chemical species of the pair polyprotic?

A) H₂S and H₂CO₃
B) H₃PO₄ and HCN
C) HC₂H₃O₂ and H₃C₆H₅O₇
D) HNO₃ and H₂C₄H₄O₆

Question 13

Which of the following is a species formed in the second step of the dissociation of H₃PO₄?

A) H₂PO₄^-
B) HPO₄^2-
C) PO₄^3-
D) H₃PO₃

Question 14

Which of the following is a triprotic acid?

A) HC₂H₃O₂
B) H₂SO₃
C) H₃PO₄
D) HNO₃

Question 15

In which of the following pairs of acids are both chemical species in the pair weak acids?

A) H₃PO₄ and H₂SO₄
B) HCN and H₂S
C) H₂CO₃ and HBr
D) HC₂H₃O₂ and HI

Question 16

Which of the following statements about weak acids is correct?

A) Weak acids always contain C atoms.
B) The percentage dissociation for weak acids is usually in the range 40-60%.
C) Weak acids can only be prepared as dilute solutions.
D) Weak acid molecules have a strong affinity for acidic hydrogens.

Question 17

Which of the following pairs of compounds and classifications is incorrectly matched?

A) HI   strong acid
B) NH₃   weak base
C) LiC₂H₃O₂   salt
D) Ca(OH)₂   weak base

Question 18

In which of the following pairs of substances would both species in the pair be written in molecular form in a net ionic equation?

A) HF and CO₂
B) LiOH and H₂
C) CO₂ and H₂SO₄
D) NH₄Cl and NaCl

Question 19

In which of the following pairs of substances would both species in the pair be written in ionic form in a net ionic equation?

A) CH₃COOH and HNO₃
B) Na₂CO₃ and Ba(NO₃)₂
C) AgCl and CO₂
D) KBr and NH₃

Question 20

The net ionic equation for the reaction Ca(OH)₂ + 2HCl ? 2H₂O + CaCl₂ is ________.

A) Ca²⁺ + 2Cl^- $\rightarrow$ CaCl₂
B) Ca(OH)₂ + 2H⁺ $\rightarrow$ Ca²⁺ + 2H₂O
C) OH^- + H⁺ $\rightarrow$ H₂O
D) 2 OH^- + 2 HCl $\rightarrow$ 2H₂O

Question 21

In the reaction below, which species will not be written as its constituent ions when the equation is expanded into the ionic equation?
Mg(OH)₂ (s) + 2HCl (aq) $\rightarrow$ MgCl₂ (aq) + 2H₂O (l)

A) HCl
B) MgCl₂
C) Mg(OH)₂ only
D) H₂O and Mg(OH)₂

Question 22

Choose the response that contains all of the spectator ions in the chemical equation below.
Pb(NO₃)₂ (aq) + H₂SO₄ (aq) $\rightarrow$ PbSO₄ (s) + 2 HNO₃ (aq)

A) Pb²⁺ and NO₃^-
B) Pb²⁺ and H⁺
C) H⁺ and SO₄^2-
D) NO₃^- and H⁺

Question 23

Complete the following acid-base reaction. What is the sum of the coefficients for the balanced molecular equation?
LiOH (aq) + H₂SO₄ (aq) ?

A) 6
B) 9
C) 12
D) 14

Question 24

Complete the following acid-base reaction. What is the sum of the coefficients for the balanced molecular equation?
BaCO₃(aq) + HNO₃(aq) ?

A) 8
B) 6
C) 9
D) 10

Question 25

Which of the following statements about the reaction of acids with metals is incorrect?

A) Acids react with many, but not all, metals.
B) Any metal below hydrogen in the activity series will dissolve in a non-oxidizing acid.
C) Hydrogen gas is produced when a metal dissolves in acid.
D) Metal atoms which dissolve in acid become positive metal ions.

Question 26

The neutralization of Cr(OH)₃ with H₂SO₄ produces which of the following products?

A) OH^-
B) H₃O⁺
C) Cr₂(SO₄)₃
D) SO₂

Question 27

A metal and a salt solution will react only if the metal going into the solution is ________.

A) above hydrogen in the activity series
B) below hydrogen in the activity series
C) above the replaced metal in the activity series
D) below the replaced metal in the activity series

Question 28

In which of the following pairs of substances will the two members of the pair not react?

A) HF and LiOH
B) PbCl₂ and H₂SO₄
C) Na₃PO₄ and HCl
D) KCl and NaI

Question 29

Which is the balanced net ionic equation for the reaction between Ni(NO₃)₂ (aq) and NaOH (aq)-

A) Na⁺ (aq) + NO₃^-(aq) $\rightarrow$ NaNO₃ (s)
B) Ni²⁺ (aq) + 2 Na⁺ (aq) $\rightarrow$ NiNa₂ (s)
C) Ni²⁺ (aq) + 2 OH^- (aq) $\rightarrow$ Ni(OH)₂ (s)
D) Ni(NO₃)₂ (aq) + 2 NaOH (aq) $\rightarrow$ Ni(OH)₂ (s) + 2 NaNO₃( aq)

Question 30

The product of [H₃O⁺] and [OH^-] in pure water, at 25 °C, is ________.

A) zero
B) always greater than 1
C) 1.00 x 10^-7
D) 1.00 x 10^-14

Question 31

Which of the following solutions is acidic?

A) [H₃O⁺] = 1.00 x 10^-3
B) [H₃O⁺] = 1.00 x 10^-11
C) [H₃O⁺] = 1.00 x 10^-9
D) [H₃O⁺] = 1.00 x 10^-8

Question 32

In a basic solution:

A) [H₃O⁺] = [OH^-]
B) [H₃O⁺] > [OH^-]
C) [H₃O⁺] < [OH^-]
D) [H₃O⁺] = 0 M

Question 33

A solution with [H₃O⁺] = 1.00 x 10^-5 would have [OH^-] equal to ________.

A) 1.00 x 10^-5
B) 1.00 x 10^-7
C) 1.00 x 10^-9
D) 1.00 x 10^-14

Question 34

The pH of a solution for which [OH^-] = 1.0 x 10^-9 is ________.

A) 1.00
B) 5.00
C) 9.00
D) -5.00

Question 35

The pH of a solution for which [H₃O⁺] = 8.3 x 10^-9 is ________.

A) 5.92
B) 9.60
C) 8.08
D) 6.00

Question 36

What is the pH of a solution that has a hydronium ion concentration of 3.98 x 10^-9 M?

A) 5.600
B) 8.400
C) 9.000
D) 3.980

Question 37

The [OH^-] and the pH of 0.035 M KOH at 25 °C are, respectively, ________.

A) 0.035 M and +1.46
B) 0.035 M and -1.46
C) 2.9 x 10^-13 M and -12.5
D) 0.035 M and +12.5

Question 38

If the pH of a solution has decreased from 5.0 to 4.0, the [H₃O⁺] ________.

A) increases by a factor of 1
B) increases by a factor of 10
C) decreases by a factor of 1
D) decreases by a factor of 100

Question 39

In a solution with a pH of 9.64, the molar concentration of the hydrogen ion would be ________.

A) 1.4 x 10^-9
B) 5.6 x 10^-10
C) 2.3 x 10^-11
D) 2.3 x 10^-10

Question 40

Which of the following does not describe an acidic solution?

A) The pH is less than 7.
B) The [OH^-] is 1 x 10^-4 M.
C) The [OH^-] is less than the [H₃O⁺].
D) The [OH^-] is 6.0 x 10^-10 M.

Question 41

A solution has a pH = 6. What is the pH of a solution that is 1000 times less acidic?

A) 12
B) 7
C) 5
D) 9

Question 42

Which of the following substances is most acidic?

A) soap, pH 9.0
B) a tomato, [OH^-] = 2.5 x 10^-10 M
C) rain water, [H⁺] = 2.0 x 10^-6 M
D) liquid bleach, [OH^-] = 1.0 x 10^-2 M

Question 43

A solution has a pH = 3.0. What is the pH of a solution that is 100 times more basic?

A) 1.0
B) 3.0
C) 5.0
D) 13.0

Question 44

The pH of a solution is 5.46. Determine the [H₃O⁺] for the solution.

A) 1.9 x 10^-5 M
B) 3.5 x 10^-6 M
C) 5.6 x 10^-4 M
D) 1.1 x 10^-6 M

Question 45

The pH of a solution is 8.11. Determine the [H₃O⁺] for the solution.

A) 7.8 x 10^-9 M
B) 1.3 x 10⁸ M
C) 1.3 x 10^-8 M
D) 8.1 x 10^-8 M

Question 46

The pH of a solution is 3.75. Determine the [H₃O⁺] for the solution.

A) 5.6 x 10³ M
B) 7.5 x 10^-3 M
C) 5.6 x 10^-11 M
D) 1.8 x 10^-4 M

Question 47

Which one of the following salts will hydrolyze to give an acidic solution?

A) NH₄Cl
B) LiNO₃
C) KC₂H₃O₂
D) Na₂S

Question 48

Which of the following compounds will not hydrolyze?

A) HF
B) H₂S
C) NaC₂H₃O₂
D) HCl

Question 49

If the pH of a solution of a salt is 10.5, the salt must be one which could be formed from the neutralization of ________.

A) a strong acid and a strong base
B) a weak acid and a strong base
C) a strong acid and a weak base
D) HCl and NaOH

Question 50

Which of the following salts will hydrolyze to give an acidic solution?

A) LiNO₃
B) NaCl
C) CH₃NH₃⁺
D) NaC₂H₃O₂

Question 51

Which is the correct net ionic equation for the hydrolysis reaction of Na₂S?

A) S^2- (aq) + H₂O (l) $\rightarrow$ HS^- + OH^- (aq)
B) S^2- (aq) + 2 H₂O (l) $\rightarrow$ HS^- (aq) + H₃O⁺ (aq)
C) Na⁺ (aq) + H₂O (l) $\rightarrow$ NaOH (aq) + H₂ (g)
D) Na⁺ (aq) + 2 H₂O (l) $\rightarrow$ NaOH (aq) + H₂O⁺ (aq)

Question 52

Which of the following pairs of substances could not function as a buffer system in aqueous solution?

A) HClO₄ and KClO₄
B) HNO₂ and NH₄NO₂
C) NaHCO₃ and Na₂CO₃
D) HF and LiF

Question 53

Which of the following pairs of substances could not function as a buffer system in aqueous solution?

A) KC₂H₃O₂ and HC₂H₃O₂
B) KHSO₃ and H₂SO₃
C) HCl and NaCl
D) K₂HPO₄ and NaH₂PO₄

Question 54

How many grams of tartaric acid, H₂C₄H₄O₆ (molar mass = 150.10

A) 1.36 g
B) 5.62 g
C) 11.2 g
D) 2.70 g

Question 55

If 12.3 mL of 0.25 M HNO₃ is required to titrate 18.4 mL of Ba(OH)₂, the molarity of the Ba(OH)₂ solution is ________.

A) 0.012 M
B) 0.80 M
C) 0.084 M
D) 2.4 M

Question 56

How many mL of a 0.100 M NaOH solution is needed to neutralize 50.00 mL of a 0.150 M solution of HC₂H₃O₂?

A) 25.0 mL
B) 37.5 mL
C) 75.0 mL
D) 100. mL

Question 57

In a titration, 35.84 mL of 0.2419 M HCl solution is required to completely neutralize 18.62 mL of Fe(OH)₃ solution. What is the molarity of the Fe(OH)₃ solution?
3 HCl + Fe(OH)₃ $\rightarrow$ FeCl₃ + 3 H₂O

A) 0.1552 M
B) 0.4656 M
C) 0.1164 M
D) 0.3492 M

Question 58

Titration of 37.22 mL of Ca(OH)₂ solution requires 31.19 mL of 0.219 M H₃PO₄ solution according to the following equation:
3 Ca(OH)₂ (aq) + 2 H₃PO₄ (aq) $\rightarrow$ Ca₃(PO₄)₂ (s) + 6 H₂O (l)
What is the molarity of the base in this reaction?

A) 0.275 M
B) 0.122 M
C) 0.184 M
D) 0.392 M

Question 59

What is the molarity of concentrated sulfuric acid, H₂SO₄?

A) 6 M
B) 18 M
C) 16 M
D) 14 M

Question 60

If 30.0 mL of 0.40 M H₂SO₄ is required to neutralize 15.0 mL of NaOH, the molarity of the NaOH solution is ________.
H₂SO₄ (aq) + 2 NaOH (aq) $\rightarrow$ Na₂SO₄ (aq) + 2 H₂O (l)

A) 1.6 M
B) 0.40 M
C) 0.80 M
D) 2.4 M

Question 61

What is the concentration of a nitric acid solution if a 10.00 mL sample of the acid requires 31.25 mL of a 0.135 M KOH to neutralize it?

A) 0.0432 M
B) 0.422 M
C) 0.844 M
D) 0.135 M

Question 62

Identify the acid (A), base (B), conjugate acid (CA) and conjugate base (CB) in each of the following reactions:

A) HSO₄^-(aq) + ClO^-(aq) → HClO (aq) + SO₄^-2 (aq)
B) H₂C₂O₄ (aq) + NH₃ (aq) → HC₂O₄^- (aq) + NH₄⁺

Question 63

Write the balanced net ionic equation for the following acid-base reaction using the simplest whole number ratio of coefficients.
H₃PO₄ (aq) + 3 LiOH (aq) → 3 H₂O (l) + Li₃PO₄ (aq)

Question 64

Write an equation for the response of a HCO₃⁻/CO₃²⁻ buffer to the addition of OH⁻ ions.

Question 65

Write an equation for the response of a HF/F⁻ buffer to the addition of H₃O⁺ ions.