Which of the following are not acids?

CH₃COOH, CO₂ , HNO₂ , HCOOH, CCl₄

Consider the following reaction: HBr + ^-C≡N ⇌ Br⁻ + HC≡N

a. What is the acid on the left side of the equation?

b. What is the base on the left side of the equation?

Consider the following reaction:

HBr + ^-C≡N ⇌ Br⁻ + HC≡N

c. What is the conjugate base of the acid on the left?

d. What is the conjugate acid of the base on the left?

Consider the following reaction:

HBr + ^-C≡N ⇌ Br⁻ + HC≡N

g. What is the conjugate base of the acid on the right?

h. What is the conjugate acid of the base on the right?

What is the conjugate acid of each of the following?

1. NH₃

2. Cl⁻

3. HO⁻

4. H₂O

What is the conjugate base of each of the following?

1. NH₃

2. HBr

3. HNO₃

4. H₂O

a. Which is a stronger acid: one with a pK_a of 5.2 or one with a pK_a of 5.8?

b. Which is a stronger acid: one with an acid dissociation constant of 3.4 × 10⁻³ or one with an acid dissociation constant of 2.1 × 10⁻⁴?

An acid has a K_a of 4.53 × 10⁻⁶ in water. What is its K_eq for reaction with water in a dilute solution? ([H₂O] = 55.5 M)

Butyric acid, the compound responsible for the unpleasant odor and taste of sour milk, has a pK_a value of 4.82. What is its Ka value? Is it a stronger acid or a weaker acid than vitamin C?

Antacids are compounds that neutralize stomach acid. Write the equations that show how Milk of Magnesia, Alka-Seltzer, and Tums remove excess acid.

a. Milk of Magnesia: Mg(OH)₂

b. Alka-Seltzer: KHCO₃ and NaHCO₃

c. Tums: CaCO₃

Draw the conjugate acid of each of the following:

a. CH₃CH₂OH

b. CH₃CH₂O⁻

c.

Estimate the pKa values of the following compounds:

c. CH₃CH₂COOH

d. CH₃CH₂CH₂N⁺H₃

a. Which is a stronger base: CH₃COO⁻ or HCOO⁻? (The pK_a of CH₃COOH is 4.8; the pK_a of HCOOH is 3.8.)

b. Which is a stronger base: HO⁻ or ^-NH₂? (The pK_a of H2O is 15.7; the pK_a of NH3 is 36.)

c. Which is a stronger base: H₂O or CH₃OH? (The pK_a of H3O+ is −1.7; the pK_a of CH₃O⁺H₂ is −2.5.)

Does methanol behave as an acid or a base when it reacts with methylamine?

For each of the acid–base reactions in [Section 2.3], compare the pK_a values of the acids on either side of the equilibrium arrows to prove that the equilibrium lies in the direction indicated.

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For each of the acid–base reactions in [Section 2.3], compare the pK_a values of the acids on either side of the equilibrium arrows to prove that the equilibrium lies in the direction indicated.

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Ethyne (HC≡CH) has a pK_a value of 25, water has a pK_a value of 15.7, and ammonia (NH3) has a pKa value of 36. Draw the equation, showing equilibrium arrows that indicate whether reactants or products are favored, for the acid–base reaction of ethyne with

a. HO^-.

Ethyne (HC≡CH) has a pK_a value of 25, water has a pK_a value of 15.7, and ammonia (NH₃) has a pK_a value of 36. Draw the equation, showing equilibrium arrows that indicate whether reactants or products are favored, for the acid–base reaction of ethyne with

b. ⁻NH₂.

c. Which would be a better base to use if you wanted to remove a proton from ethyne, HO⁻ or ^-NH₂?

Which of the following bases can remove a proton from acetic acid in a reaction that favors products?

HO⁻ CH₃NH₂ HC≡C⁻  CH₃OH H₂O Cl⁻

Calculate the equilibrium constant for the acid–base reaction between the reactants in each of the following pairs:

c. CH₃NH₂ + H₂O

d. CH₃N⁺H₃ + H2O

Rank the ions (⁻CH₃, ⁻NH₂, HO⁻, and F⁻) from most basic to least basic.

Rank the carbanions shown in the margin from most basic to least basic.

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Which is a stronger acid?

Which reaction in Problem 23 has the smallest equilibrium constant?

Rank the following from strongest base to weakest base:

b.

Which is a stronger acid?

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d. CH₃CH₂CH₂OH or CH₃CH₂CH₂SH

Which is a stronger acid?

c. CH₃OCH₂CH₂CH₂OH or CH₃CH₂OCH₂CH₂OH

d.

Which is a stronger base?

a.

b.

If HCl is a weaker acid than HBr, why is ClCH₂COOH a stronger acid than BrCH₂COOH?

For each of the following compounds, indicate the atom that is protonated when an acid is added to a solution of the compound.

a.

b.