Chapter 10

In the following reaction, which substance is the base and which substance is the conjugate base? HClO3(aq) + H2O(l) ClO3-(aq) + H3O+(aq) The base is H2O and the conjugate base is H3O+. The base is HClO3 and the conjugate base is H3O+. The base is H2O and the conjugate base is ClO3-. The base is HClO3 and the conjugate base is ClO3-.

The base is H2O and the conjugate base is ClO3-.

Which statement(s) about conjugate acids and bases is true? The conjugate base of F- is H2O. The conjugate base of F- is HF. The conjugate acid of F- is HF. None of these is true.

The conjugate acid of F- is HF.

Write the formula for the conjugate acid of HAsO42-. AsO43- H2AsO4- H3AsO4 HAsO4-

H2AsO4-

Complete this sentence. Ca(OH)2 is a ________ and H2CO3 is an ________. base; base acid; base base; acid acid; acid

base; acid

A solution of LiF would be acidic. basic. neutral. non-ionic.

basic.

The names of the acid H3PO4 and the base KOH are phosphoric acid and potassium hydroxide. hydrogen phosphate and potassium base. hydrogen phosphoric acid and potassium hydroxide. phosphoric acid and potassium oxide base.

phosphoric acid and potassium hydroxide.

A 15.0 mL sample of HCl is placed in a flask. Titration required 35.0 mL of 0.22 M NaOH. What is the molarity of the HCl in the sample? HCl(aq) + NaOH → NaCl(aq) + H2O(l) 0.0077 M HCl 0.51 M HCl 0.22 M HCl 0.12 M HCl

0.51 M HCl

Complete and balance the following equation. What coefficient will calcium metal have? Ca(s) + HCl(aq) → 1 2 3 4

1

What is the [H3O+] if the solution has a hydroxide ion concentration of 8.1 × 10-2 M? 8.1 × 10-16 M 1.2 × 10-13 M 8.1 × 1012 M 1.2 × 1015 M

1.2 × 10-13 M

The pH of a solution is 3.81. What is the hydronium ion concentration? 2.8 × 10-3 M 6.5 × 10-11 M 1.5 × 10-4 M 4.5 × 10-8 M

1.5 × 10-4 M

If the hydroxide ion concentration of a solution is 3.2 × 10-4 M, what is the pH of the solution? 3.49 2.7 × 10-6 M 3.1 × 10-11 10.51

10.51

Balance the following neutralization reaction. What coefficient will HCl have? Mg(OH)2(s) + HCl(aq) → MgCl2(aq) + H2O(l) 1 2 3

2

What is the [OH-] if the solution has a hydronium ion concentration of 4.3 × 10-4 M? 2.3 × 10-19 M 2.3 × 10-11 M 2.3 × 1017M 4.3 × 1010 M

2.3 × 10-11 M

What is the pH of a solution whose hydronium ion concentration is 2.6 × 10-3 M? 2.585 2.6 2.59 3

2.59

How many milliliters of 0.20 M NaOH are required to neutralize completely 8.5 mL of 0.50 M H2SO4? H2SO4(aq) + 2 NaOH(aq) → Na2SO4(aq) + 2 H2O(l) 43 mL 0.0086 mL 0.043 mL 0.0043 mL

43 mL

If the pH of a solution is 11.81, what is the hydroxide ion concentration? 1.5 × 10-12 M 2.9 × 10-2 M 6.5 × 1011 M 6.5 × 10-3 M

6.5 × 10-3 M

Which statement(s) is true? A. Acids produce HO- in water. B. Bases have a soapy feel. C. Bases turn litmus paper red. D. Acids have a sour taste. B and C B and D A and B C and D

B and D

What is the pH of a solution whose hydronium ion concentration is 2.6 × 10-9 M? 5.41 14.00 2.69 8.59

8.59

Which statements concerning an Arrhenius acid is true? Acids neutralize bases in a reaction that produces water and a salt. Acids react with carbonates and bicarbonates to yield CO2, H2O, and the salt of the metal. Acids react with active metals to yield hydrogen gas (H2) and the salt of the metal. All of these statements are true.

All of these statements are true.

Which of these solute pairs will form a buffer solution? A. KOH and KCl B. H2CO3 and NaHCO3 C. KF and KCl D. HCl and NaOH A B C

B

Which is the strongest acid in this group? H3O+ HF HS- HCN H3O+ HF HS- HCN

H3O+

The strong acids include HBr, HNO2, and H2SO4. HCl, HBr, and HF. HCl, HBr, and H2SO3. HI, HNO3, and HClO4.

HI, HNO3, and HClO4.

What is the formula for nitric acid? HNO HNO2 HNO3 HNO4

HNO3

Which of the following salt solutions would you expect to have a pH of 7.0 LiF Na3PO4 LiBr NaCN

LiBr

For the following reaction, what statement is true? HCN(aq) + H2O(l) CN-(aq) + H3O+(aq) More HCN is present than water. More HCN is present than CN-. More hydronium ion, H3O+, is present than water. Answers B and C are both true.

More HCN is present than CN-.

When NH4Cl dissolves in water, the ammonium ion, NH4+, donates a proton to water. What is the conjugate base in this reaction? NH4+(aq) + H2O(l) NH3(aq) + H3O+(aq) H2O NH3 NH4+ H3O+

NH3

Which of the following salts would be expected to form an acidic solution? NH4Br KCN NaNO3 KClO4

NH4Br

Which of the following would act as a buffer system? Na2CO3 NaHCO3 and H2CO3 NaOH and NaNO3 HCl

NaHCO3 and H2CO3

What is true of a typical buffer system? It maintains a pH of 7.0 It contains a weak base only. It contains a strong acid and its salt. None of these is true.

None of these is true.

Write the formula for the conjugate base of HSO3-. HSO2- H2SO3 SO32- SO2-

SO32-

The hydronium ion concentrations of five solutions are shown below. Which solution(s) is(are) acidic? Solution A: 1.5 × 10-1 M Solution B: 1.5 × 10-3 M Solution C: 1.5 × 10-4 M Solution D: 1.5 × 10-7 M Solution E: 1.5 × 10-11 M All of the solutions are acidic. Solution E is acidic. Solutions A, B, C, and D are acidic. Solutions A, B, and C are acidic.

Solutions A, B, C, and D are acidic.

A weak base donates many protons. accepts many protons. accepts few protons. donates few protons.

accepts few protons.

A substance that forms hydroxide ions in water and/or accepts protons is a(n) base. neutralization. acid. solution.

base.