Acid Base Equilibrium Practice Problems

Propose suitable products for the following acid-base reactions:

Also, predict the direction of equilibrium for each reaction.

Which of the given solvents will be compatible with the acids and bases involved in the following reactions (Ignoring any side reactions)?

Solvent choices = diethyl ether, ethanol, and water.

a. CH₃CH₂Li + CH₃—C≡C—H → CH₃—CH₃ + CH₃—C≡CLi 

b. CH₃CH₂Li + (CH₃)₂CH—OH → CH₃—CH₃ + (CH₃)₂CH—OLi 

The acid-catalyzed hydrolysis of 6-cyclopentylhexyl 4-phenylbutanoate yields 4-phenylbutanoic acid and 6-cyclopentylhexanol. Complete the simplified flow chart for separating the carboxylic acid from the alcohol product by identifying X1 to X6.

Using the given K_eq value, identify the weakest acid and the weakest base in the reaction given below.

Using the given equilibrium constant, identify the weakest acid and the weakest base in the reaction given below.

Using the given equilibrium constant value, identify the weakest acid and the weakest base in the following reaction.

Using the given equilibrium constant value, identify the strongest acid and the strongest base in the given reaction.

Using the given equilibrium constant value, identify the strongest acid and the strongest base in the following reaction.

Using the given equilibrium constant values, identify the strongest acid and the strongest base in the reaction shown below.

Use the K_eq values mentioned with each of the following equations to determine how much stronger acid is phenol than acetamide.

Use the K_eq values stated in each of the following equations to determine the factor by which cyanomethanide is a stronger base than pyrrolide.

Which of the bases given below are able to deprotonate propanoic acid (pK_a = 4.88) in an acid-base reaction that favors the formation of products?
(i) CH₃O⁻ (pK_a of CH₃OH = 15.9)
(ii) NH₃ (pK_a of NH₄⁺ = 9.4)
(iii) CH₃C≡C⁻ (pK_a of CH₃C≡CH = 25)
(iv) CH₃CH₂OH (pK_a of CH₃CH₂OH₂⁺ = −2.5)
(v) H₂O (pK_a of H₃O⁺ = −1.7)
(vi) Br⁻ (pK_a of HBr = −9)

Create a scheme to separate the following compounds from a mixture. 1.0 M HBr, 1.0 M KOH, water and diethyl ether are available for you to use.

An acid-base equilibrium favors the formation of the weaker acid. Which of the following reactions favor the formation of products?

Give the products of the acid-base reaction shown below. Use the p K_a values to determine whether the reaction favors the product or reactant side at equilibrium. (pK_a of the acid on the reactant side is  4.87, p K_a of the acid on the product side is 16.0)

Draw the products of the acid-base reaction shown below and use the p K_a values to indicate whether equilibrium favors the reactants or the products. (pK_a of the acid on the reactant side is 16.5, p K_a of the acid on product side is 36.0)

Which of the compounds given below can be deprotonated by CH₃O⁻ in an acid-base reaction that favors product formation? (pK_a of CH₃OH = 15.9)
(i) HCOOH (pK_a = 3.7)
(ii) CH₃NH₂ (pK_a = 40)
(iii) NH₄⁺ (pK_a = 9.4)
(iv) HC≡CH (pK_a = 25)

For each pair of reactions, determine which reaction favors the formation of products the most.

Reaction A: HCOOH + NH₃ ⇌ HCOO^— + NH₄⁺

Reaction B: CH₃COOH + NH₃ ⇌ CH₃COO^— + NH₄⁺

Ethoxide cannot be used to deprotonate cyclohexane in a reaction that favors the formation of a carbanion. Explain why this is true.

An acid-base equilibrium favors the formation of the weaker acid. Which of the following reactions favor the formation of products?

Complete the following acid-base reactions and predict the equilibrium positions of these reactions using the information given in the table.

a. CH₃OH + NaNH₂
b. ⁻CN + CH₃COOH
c. CH₃CH₂OH + HCOO⁻

Using the pK_a values of acetic acid and benzoic acid, predict whether the equilibrium will favor the products or the reactants in the following reaction.

Phenols are less acidic than carboxylic acids and can only be deprotonated using a strong base. Explain how acid-base extraction can be used to isolate the pure compounds from the mixture of acetophenone (acetylbenzene), 2-methylphenol, and o-toluic acid (2-methylbenzoic acid).

How can acid-base extraction be utilized to separate the mixture of given compounds?

Benzylamine, m-cresol (3-methylphenol), p-toluic acid, and 2-phenylethanol.

For each of the following Brønsted–Lowry acid–base reactions (i): 3-methylpyridine + 4-chlorophenol and (ii): 3-methylpyridine + 4-chlorobenzoic acid, write the products of a transfer of the most acidic proton on the acid to the most basic site on the base. Also, determine whether the reactants side or the products side is favored in each of the acid-base reactions by using the pK_b values for the bases and the pK_a values for the acids.

Some equations of acid-base reactions are given below. Write the products in each case if any significant reaction is possible.

a. CH₃—C≡C—H + NaOH
b. CH₃—C≡C—H + CH₃Li
c. CH₃—C≡C—H + NaNH₂

Consider the following acid-base reaction.

Write the products, identify the direction that is favored by the equilibrium, and give an explanation for your answer.

Consider the following acid-base reaction.

Write the products, identify the direction that is favored by the equilibrium, and give an explanation for your answer.

Complete the following equilibrium and predict the favored side.

Consider the following pK_a values:

Hydrogen cyanide (HC≡N) has a pK_a value of 9.1, ethanethiol (CH₃CH₂SH) has a pK_a value of 10.5, and methanamine (CH₃NH₂) has a pK_a value of 40.

Provide the equation for the acid–base reaction of hydrogen cyanide and CH₃CH₂S^- with the arrows that indicate which side is favored. Identify the better base between ethanethiol and methanamine to remove a proton from hydrogen cyanide.

For the acid-base reactions below, prove that the equilibrium lies in the direction indicated in the reactions by comparing the pK_a values of the acids on both sides of the equilibrium arrow.

For the given acid-base reactions below, prove that the equilibrium lies in the indicated direction in the given reactions by comparing the pK_a values of the acids.

Draw the acid-base reaction of butyne (CH₃CH₂C≡CH) and ^-OH that shows the correct equilibrium arrows, which indicate which side of the equation is favored. [CH₃CH₂C≡CH: pKa = 25.0; H₂O: pKa = 15.7]

For the given carboxylic acid and protonated amine, determine the pH at which the acid would dissolve in the water layer and the pH at which the protonated amine would dissolve in the ether layer.

Write an acid-base reaction given the following reactant.

CCl₃CH₂CH₂S^- + ClCH₂CH₂CH₂CH₂SH

Label the conjugate acids and bases based on the order it is written in the reaction. Predict whether the equilibrium favors the reactants or products.

(i) Complete the acid-base reaction, and (ii) label and explain whether the reactant or the product is favored at equilibrium.

(a) Complete the acid-base reaction and (b) indicate and explain which is favored at equilibrium (reactant or product).

Complete the acid-base reaction given below. Label each reaction's conjugate acid and base, and predict whether the equilibria favor reactants or products.

(i) H₂Te + NaNH₂ ⇌

(ii) F₃CCH₂CH₂O^- + FCH₂OH ⇌

By using the given pK_a values for the conjugate acids of the given bases in the following hypothetical reaction, determine which side of the equilibrium reaction would be favored.

Consider the given acid-base reaction: 

Using pK _a, determine which side of the reaction is favored.

What is the K_eq for the reaction of an unknown acid with water in a dilute solution?   K_a of this acid is 4.93 × 10 ⁻¹³. Use the molarity of water as [H ₂O] = 55.5 M.

Choose the appropriate solvents for the following reactions considering that each involves acids and bases (ignore the other possible reactions that can occur).

Choices of solvents: hexane, CH₃(CH₂)₄CH₃; water, H₂O; methylamine, CH₃NH₂; diethyl ether, (CH₃CH₂)₂O; methanol, CH₃OH

For each of the compounds listed below in their acidic forms, determine what would be their predominant state at a solution with pH = 7:

a. HCl (pK_a = -7)

b. HNO₃ (pK_a = -1)

Determine the direction of equilibrium for the following acid-base reactions. (The pK_a of H₂CO₃ is 6.4.)

H₂CO₃ + OH⁻ ⇌ HCO₃⁻ + H₂O

NH₄⁺ + HCO₃⁻ ⇌ NH₃ + H₂CO₃

At what pH will over ninety-nine percent of propionic acid (C₂H₅COOH with pK_a=4.87) exist in a form that carries a charge?