SmartBook Assignment Chapter 17: Acids, Bases, and Salts

A salt consisting of the _____ of a strong acid and the _____ of a strong base yields a neutral solution.

anion; cation

How does a conjugate acid differ from its conjugate base? Select all that apply.

-The conjugate acid of a neutral base will have a charge of +1. -The conjugate acid has one more H than its conjugate base. -A conjugate base may be positively charged, neutral, or negatively charged.

Which of the following solutions of HCN will have the greatest percent ionization?

0.00010 M

The [OH-] of a 0.010 M Ba(OH)2 solution is _____ M and the pOH is equal to _____.

0.020, 1.70

Arrange the following compounds in order of increasing acid strength (weakest at the top to strongest at the bottom of the list).

1. H2O 2. HF 3. HBr

Rank the following 0.1 M salt solutions in order of increasing pH (lowest pH at the top of the list).

1. NaHSO4 2. NH4NO3 3. NaHCO3 4. Na2CO3

Which of the following statements correctly describe salt hydrolysis?

The ions produced by dissociation of a salt in water react with H2O. Salt hydrolysis may cause the pH of the resulting solution to be above or below 7.00. Both the anion and the cation of a water-soluble salt may interact with water.

Which of the following factors will affect the relative strength of oxoacids? Select all that apply.

The number of O atoms attached to the central nonmetal atom The electronegativity of the central nonmetal atom

A salt in which the anion is the conjugate _____ of a weak _____ will produce a basic solution. (Assume that the cation does not hydrolyze.)

base, acid

A Bronsted-Lowry acid is a proton _____ and must therefore contain at least one ionizable _____ atom in its formula.

donor; hydrogen

Acidic solutions have a _____ pOH than basic solutions.

higher

Select the most likely pOH value for a basic aqueous solution.

pOH = 3.00

The degree of ionization for a weak monoprotic acid HA is given by the expression ([H+]eq/[HA]0)× 100%. This is called the _____ ionization and is a measure of acid strength.

percent, percentage, or %

Hydrated _____ metal cations act as weak acids because these metal ions are so successful at withdrawing electron density from the O-H bond of water, thus facilitating the loss of H+ to the solvent water to form H3O+.

small, highly charged

In the reaction illustrated here, a proton is transferred from _____, which is the Bronsted _____, to _____, which acts as the Bronsted _____.

water, acid, ammonia, base

In general, the stronger an acid is, the _____ its conjugate base will be. The stronger the acid, the more the equilibrium shown below will favor the formation of the _____. HA + H2O ⇌ H3O+ + A-

weaker, conjugate base

Calculate the Kb value for the acetate ion (CH3COO-) if the Ka value for acetic acid (CH3COOH) is 1.8 x 10^-5.

5.6 × 10^-10

Which of the following statements correctly describe the acid-base properties of a 0.10-M solution of ammonium cyanide (NH4CN)? Select all that apply. Ka of NH4+ = 5.6 x 10^-10 and Kb of CN- = 1.8 x 10^-5.

CN- will behave as a base when it reacts with water. Both NH4+ and CN- will hydrolyze (react with water) in aqueous solution. The solution will be basic.

Which statement best explains the trend in acid strength: H2SO4 > H2SO3 > H2SeO3?

H2SO4 is stronger than H2SO3 because it has more O atoms.

Which of the following acids are polyprotic?

H3PO4 H2SO3

Select ALL the weak acids from the following list.

HF CH3CH2COOH HCN

Which of the following compounds are strong acids? Select all that apply.

HI HClO4 H2SO4

In order to determine whether a solution of NH4C2H3O2 is acidic, basic, or neutral, what two values could be compared?

Kb of CH3COO- Ka of NH4+

A salt in which the cation is the conjugate acid of a weak base will be ______. (Assume that the anion does not hydrolyze.)

acidic

In general, nonmetal oxides tend to be _____ while metal oxides tend to be _____.

acidic, basic

Calculate the pH and [H3O+] of a 0.080 M solution of NaOH.

pH = 12.90 [H3O+] = 1.3 × 10^-13 M

A 0.10 M CH3COOH solution has a [H3O+] = 1.3 × 10^-3 M. What is the percent ionization of CH3COOH with a Ka = 1.8 × 10^-5?

1.3%

A 0.15 M solution of butanoic acid, CH3CH2CH2COOH (or C3H7COOH), contains 1.51 × 10^-3 M H3O+. What is the Ka of butanoic acid?

1.5 × 10^-5

What is the pH of a 0.25 M solution of ethanolamine (Kb = 3.2 × 10^-5)?

11.45

Nitrous acid, HNO2, has a Ka of 7.1 × 10^-4. What is the [H3O+] in a 0.60 M solution of HNO2?

2.1 × 10^-2 M

Calculate the Ka value for the anilium ion (C6H5NH3+) if Kb for aniline (C6H5NH2) is 4.0 x 10^-10.

2.5 × 10^-5

Which of the following statements correctly describe amphoteric hydroxides? Select all that apply.

Al(OH)3 is an amphoteric hydroxide. Amphoteric hydroxides react with both acids and bases.

Select all the statements that correctly describe the acid-base behavior of oxides.

Alkali metal oxides are basic. Some metals from Group 13(3A) form amphoteric oxides. Most nonmetal oxides are acidic.

A compound that contains one or more ionizable _____ atoms as well as one or more available _____ electron pairs can act as either an acid or a base, depending on the reaction.

Blank 1: H or hydrogen Blank 2: lone, nonbonding, non-bonding, nonbonded, non-bonded, unshared, or unbonded

A Bronsted-Lowry base is a proton _____ . A Bronsted-Lowry base must contain an available _____ pair of _____ in its formula in order to form a _____ bond to H+.

Blank 1: acceptor Blank 2: lone , nonbonded, nonbonding, non-bonding, non-bonded, unshared, or unbonded Blank 3: electrons Blank 4: covalent, single, or sigma

An amphoteric substance can behave as either a(n) _____ or a(n) _____.

Blank 1: acid or Bronsted acid Blank 2: base or Bronsted base

An acid donates a proton to form its conjugate _____, which therefore has one less _____ atom and one more _____ charge than its acid.

Blank 1: base Blank 2: H or hydrogen Blank 3: negative, minus

The strength of a weak base is indicated by its _____ ionization constant Kb. The greater the value of Kb, the _____ the base.

Blank 1: base Blank 2: stronger

An acid can be defined as a substance that loses one or more H+ ions when dissolved in water. An H+ ion is a hydrogen atom that has lost a(n) _____ and is therefore just a(n) _____. The H+ ion is not an isolated ion, but interacts strongly with H2O to produce the _____ ion, which has the formula H3O+.

Blank 1: electron Blank 2: proton, hydron, or cation Blank 3: hydronium or H3O+

When an ionic compound dissociates in water, the separated ions may react with H2O to produce H3O+ or OH- ions. This process, known as salt _____, may affect the _____ of the salt solution.

Blank 1: hydrolysis Blank 2: pH, acidity, or basicity

The autoionization of water is a process where water ionizes very slightly to form _____ ions and _____ ions. (Remember to include charges for the ions but no symbols to indicate super- or sub-scripts.)

Blank 1: hydronium, H3O+, H+, or hydrogen Blank 2: hydroxide, OH-, or HO-

The strength of an acid is measured by its tendency to _____ and produce _____ ions in aqueous solution.

Blank 1: ionize or dissociate Blank 2: hydrogen, hydronium, H+, or H3O+

An acid-base reaction occurs when one species loses a(n) _____ and another species simultaneously _____ a proton. An acid-base reaction can therefore be viewed as a proton-_____ process.

Blank 1: proton, H+, or hydrogen ion Blank 2: accepts, takes, or gains Blank 3: transfer or exchange

The two factors that influence the extent of ionization of an acid are the _____ and _____ of the HX bond, where HX is the general formula of an acid.

Blank 1: strength, bond strength, or weakness Blank 2: polarity

A(n) _____ acid is one that ionizes only slightly in water, whereas a(n) _____ acid ionizes completely.

Blank 1: weak Blank 2: strong

Select all the compounds in the following list that are strong bases.

Ca(OH)2 NaOH

Which of the following statements correctly describe carboxylic acids, represented by the general formula RCOOH? Select all that apply.

Carboxylic acids are organic acids represented by the general formula RCOOH. Carboxylic acids are weaker acids than hydrohalic acids such as HCl. As R changes, the strength of the acid changes.

Which of the following anions will produce a neutral solution in water? Select all that apply, and assume that any associated cations do not affect the pH.

Cl- I- NO3-

Which of the following oxides will NOT produce a basic solution in water?

Cl2O

The Ka values for CH3COOH and ClCH2COOH are 1.8 x 10^-5 and 5.6 x 10^-2, respectively, at 25oC. Select the correct statement about the relative strengths of these acids.

ClCH2COOH is stronger than CH3COOH.

Which of the following are valid assumptions used in solving weak-acid equilibrium problems? Select all that apply.

For very weak acids (Ka < 10^-4) at concentrations greater than 0.10 M, [HA]eqm ≈ [HA]0, the original acid concentration. The [H3O+] from water is negligible.

Which of the following formulas can be used to represent a hydrogen ion in aqueous solution?

H+ H3O+

Which of the following statements correctly explains why even distilled and deionized H2O contains some ions?

H+ can be transferred from one H2O molecule to another, forming H3O+ and -OH ions.

Which of the following statements accurately describe the characteristics of polyprotic acids? Select all that apply.

In calculations involving polyprotic acids we generally only take into account H3O+ formed from the first ionization. Polyprotic acids are generally weak acids. A polyprotic acid has more than one ionizable proton.

Which of the following statements correctly describe the relative strengths of acids and bases, and of conjugate acid-base pairs? Select all that apply.

Iodide ion, the conjugate base of HI, is a weak base. CH3COO- is a relatively stronger base than Cl3CCOO-.

The pH of a salt solution containing a small, highly charged metal cation is influenced by the hydrolysis reaction of the metal ion. Which of the following statements correctly explain the hydrolysis reaction of these metal cations? Select all that apply.

Small, highly charged metal cations accept electron pairs from water molecules and form hydrated ions. A hydrated metal ion produces an acidic solution because the metal ion withdraws electron density from the O-H bond, facilitating loss of H+.

If the pH of a 0.010 M solution of a strong base is 12.30, what is the identity of the base?

The base could be Ba(OH)2.

Calculate and compare the pH values for 0.10 M solutions of NH4Br (Ka 5.6 × 10^-10) and Al(NO3)3 (Ka 1.3 × 10^-5). Which of the following statements correctly describe the acidity of these solutions? Select all that apply.

The pH of the Al(NO3)3 solution is 2.94. The NH4Br solution has a higher pH than the Al(NO3)3 solution.

Which of the following statements accurately describe Bronsted-Lowry acid-base reactions? Select all that apply.

The reactants and products contain an acid and a base. Some species can act as either an acid or a base depending on the other species present.

Calculate [OH-] in a solution that has [H3O+] = 6.7 × 10^-2 M. Is the solution acidic or basic?

The solution is acidic. 1.5 × 10^-13 M

When calculating the pH of a weak acid or weak base solution, we assume that the [H3O+] or [OH-] due to ionization is negligible compared to the concentration of acid or base. When is this assumption justified?

When the acid/base shows less than 5% ionization

Oxoacids have the general formula illustrated, where the number of bonds to the central element E can vary. For the same element E, acid strength will _____ as the number of O atoms increases. For the same number of O atoms, acid strength increases as the _____ of element E increases.

increase; electronegativity

When calculating the pH of a weak acid solution it is justified to assume that [H3O+] derived from the acid is negligible when the [H3O+] is less than _____% of the initial acid concentration.

5 or five

A 0.10 M solution of HCN (Ka = 4.9 × 10^-10) is 7.0 × 10^-3 % ionized. What is the pH of this solution?

5.15

Which of the following statements does NOT describe a type of weak acid?

All hydrohalic acids in Period 3 or below

The product of a Lewis acid-base reaction is (CH3)2OBF3. Select all the statements that correctly describe this reaction.

An empty 2p orbital on B accepts an electron pair from O. BF3 accepts an electron pair in this reaction.

Which of the following species are Lewis acids? Select all that apply.

BF3 SO3 Cu2+

A salt consisting of a small, highly charged metal cation and the anion of a strong acid yields a(n) _____ solution.

acidic

Which of the following options correctly describe the structural characteristics of strong and weak bases? Select all that apply.

Compounds that contain electron-rich N are weak bases. Amines such as CH3CH2NH2 are weak bases. Soluble hydroxides are strong bases.

Select all the correct statements regarding percent ionization and [H3O+]eq.

Concentration of [H3O+]eq of a weak acid increases as [HA]initial increases. Percent ionization of a weak acid increases as concentration decreases.

Finding the pH of a weak base solution is very similar to that for a weak acid. What is the only step that is necessary in the calculation of pH of a weak base and not a weak acid?

Convert [OH-] to [H3O+].

Which of the protons depicted in the structure of acetic acid is considered acidic or ionizable?

D

True or false: For any acid-base reaction, Ka x Kb = Kw for the reacting acid and base.

False

True or false: The conjugate base of a weak acid will always be a strong base.

False

Which of the following is NOT a conjugate acid-base pair?

H2PO4-/PO43-

Which of the following statements correctly describes the relative strength of binary acids?

H2S is a stronger acid than H2O.

Which of the following statements correctly explain the relative strengths of the oxoacids shown: HBrO < HClO < HClO2 < HClO3? Select all that apply.

HBrO is weaker than HClO because Br is less electronegative than Cl. HClO3 is stronger than HClO2 because HClO3 has more O atoms.

Which of the following salt solutions will be basic, assuming that all have concentrations of 0.1 M? Select all that apply.

KCH3COO NaCN

Which of the following options correctly describe the ionization constant Ka? Select all that apply.

Ka is the acid ionization constant. [H2O] is not included in the Ka expression for a particular acid.

Which of the following statements correctly describe the acid-base properties of a 1.0-M solution of methylammonium fluoride (CH3NH3F)? Select all that apply. Ka of HF = 7.1 × 10^-4 and Kb of CH3NH2 = 4.4 × 10^-4

Ka of CH3NH3+ = 2.3 × 10^-11 The solution will be slightly acidic because Ka of CH3NH3+ > Kb of F-. Both CH3NH3+ and F- will hydrolyze (react with water) in aqueous solution.

Which of the following types of substances are classified as acids only under the Lewis definition? Select all that apply.

Molecules with electron deficient central atoms Molecules that contain a polar multiple bond

Select the statement that correctly explains why it is reasonable to assume that for a weak acid [HA] at equilibrium is approximately equal to [HA]init under most circumstances.

Most molecules of the weak acid remain unionized at equilibrium.

What is the conjugate base of HNO2 if it reacts as a Bronsted acid in H2O?

NO2-

The hydrogen phosphate ion, HPO42-, can act as both a Bronsted acid and Bronsted base in water. Select all the options that correctly describe the reaction that occurs when HPO42- acts as a Bronsted base in water.

OH- is one of the products. H2PO4- is one of the products. H2O acts as the Bronsted acid.

Which of the following nonmetal oxides produce a weak acid when dissolved in water? Select all that apply.

P4O10 CO2

Which of the following statements is NOT a characteristic of polyprotic acids?

Polyprotic acids are generally strong acids in their first ionization.

Consider two solutions of the weak acid HCN, one with concentration 0.10 M and one with concentration 0.010 M. Select the statements that correctly describe these solutions.

The 0.010 M solution will have a higher percent ionization. The 0.10 M solution will have a higher [H3O+].

An aqueous NaCl solution was found to have a pH = 7.00. Select all the statements that correctly describe this solution.

The NaCl solution was neutral. Neither Na+ nor Cl- reacts with water.

Which of the following statements correctly describe the relationship between the species in the reaction shown? Select all that apply.

The base in the forward reaction is CH3NH2. B and D are a conjugate acid-base pair. HSO3- is the conjugate acid of SO3^2-.

Which statement most clearly explains the relationship between an acid and its conjugate base?

The conjugate base of a weak acid may react with water to a greater extent than the acid itself does.

Which of the hydrogens in chloroacetic acid is(are) considered acidic or ionizable?

The hydrogen bonded to oxygen

Calculate [H3O+] in a solution with a [OH-] = 3.0 × 10^-4 M. Is the solution acidic or basic?

The solution is basic. 3.3 × 10^-11 M

Which of the following options correctly describe the behavior of strong and weak acids (general formula HA) in aqueous solution? Select all that apply.

The solution of a strong acid will have a negligible concentration of unionized HA molecules. A weak acid is a weak electrolyte.

Select all the options that correctly account for the behavior of NH4Cl in aqueous solution.

The solution will have a pH < 7.00. NH4+ + H2O ⇌ NH3 + H3O+

Which of the following statements correctly describe the relationship between a weak acid or base and its conjugate base or acid? Select all that apply.

The stronger a base is, the more strongly the formation of its conjugate acid is favored. The weaker an acid is, the stronger its conjugate base will be.

Select all the statements that correctly describe the acid-base behavior of H2O.

Water is amphoteric. In aqueous HCl, water acts as a Bronsted base. In aqueous NH3, water acts as a Bronsted acid.

Consider a 0.10 M CH3COOH solution (Ka = 1.8 x 10^-5). Which statement is correct about this system at equilibrium?

[H3O+] = [CH3COO-]

In equilibrium calculations involving a weak acid it is reasonable to approximate that _____.

[HA]equilibrium ≈ [HA]initial

Which of the following gives the correct mathematical operation required to calculate the concentration of hydroxide ions in a solution having a pOH of 9.38?

[OH-] = 10^-9.38

Which of the following options correctly describe a solution with a pH = 8.00? Select all that apply.

[OH-] > [H3O+] The solution is basic.

Which statements are correct when calculating Kb of a 0.040 M NH3 solution with a pH = 10.93 at 25°C? Select all that apply.

[OH-] may be calculated from pOH [NH4+]eq = [OH-]eq and [NH3]eq = [NH3]initial - [OH-]eq

A Lewis acid is any species that _____ an electron pair, whereas a Lewis base is a species that _____ an electron pair.

accepts; donates

Like other metal hydroxides, amphoteric hydroxides react with strong acids to produce metal ions and water. However, amphoteric hydroxides also react with _____ to produce complex hydroxides bound to the metal ion.

bases

In a Bronsted-Lowry acid-base reaction, the acid reacts to form its _____ and the base will form its _____.

conjugate base; conjugate acid

In an aqueous solution at a given temperature, the product [H3O+][OH-] has a _____ value. This product is equal to _____ at 25oC.

constant, 1.0 x 10^-14

The product of a Lewis acid-base reaction contains a new bond called a _____ covalent bond.

coordinate

A Lewis acid-base reaction results in the donation of a pair of electrons from the base to the acid in the formation of a(n) _____ bond.

coordinate covalent

Given the ion-product constant for water Kw = [H3O+][OH-], as the concentration of hydronium increases the concentration of hydroxide _____.

decreases

The two types of strong acids are binary acids containing hydrogen bonded to a(n) _____ atom and oxoacids in which the number of O atoms exceeds the number of ionizable protons by _____ or more.

halogen; 2

The stronger the acid, the _____ the [H3O+] at equilibrium and the _____ the value of Ka.

higher; larger

As the initial concentration of a weak acid decreases, the percent ionization of the acid ______.

increases

For solutions with the same initial concentration of acid HA, the smaller the value of Ka, the ______ the % ionization and thus the ______ the acid.

lower, weaker

When [H3O+] = [OH-], the solution is _____.

neutral or neutralized

Calculate the pH and [OH-] of a solution of a 1.5 M solution of HCl.

pH = -0.18 [OH-] = 6.7 × 10^-15 M

Which of the following mathematical relationships are correct for an aqueous solution at 25°C? Select all that apply.

pH = -log[H3O+] pOH + pH = 14.00

Acid ionization is represented by the general equation HA + H2O (l) ⇌ H3O+ (aq) + A- (aq) For a strong acid the equilibrium lies far to the _____ and [H3O+] is much _____ than [HA]. For a weak acid, on the other hand, the equilibrium lies far to the _____ and [H3O+] is much _____ than [HA].

right, higher, left, lower