Question 1

The following represents the structure of a hydronium ion.

Accepted Answer

Since there is no way for the AI to display the image referenced in the question, we cannot confirm the structure of the hydronium ion. However, hydronium ions are commonly represented as H3O+ with a trigonal pyramidal structure.

Question 2

The pK_a of lactic acid is 3.86, an equimolar solution of lactic acid and potassium lactate will have a pH of 7.72.

Accepted Answer

The correct value of pK_a for lactic acid is 3.86, which means that at pH 3.86, half of the lactic acid molecules will be dissociated into lactate and hydrogen ions. At pH 7.72, most of the lactic acid will be in the form of lactate ions, but not necessarily in an equimolar mixture with lactic acid. Therefore, the statement is false.

Question 3

The following is an accurate description of the ionization of HBr in water.

Accepted Answer

False

Question 4

A solution is 0.10 M in ascorbic acid (Vitamin C), H₂C₆H₆O₆, and 0.10 M in sodium ascorbate, NaHC₆H₆O₆. When base is added to the solution, H₂C₆H₆O₆ neutralizes the added base.

Accepted Answer

This solution is a buffer system, and when a base is added, the weak acid (ascorbic acid) neutralizes it.

Question 5

Consider the following reaction. CH₃OH(l) + CH₃OH(l) CH₃O^-(l) + CH₃OH₂⁺(l) This reaction could be classified as both an autoionization reaction and a proton transfer reaction.

Accepted Answer

The answer of Consider the following reaction. CH₃OH(l) + CH₃OH(l) ...

Question 6

A solution composed of HCl and NaCl would produce an effective buffer.

Accepted Answer

A buffer solution must have both a weak acid and its conjugate base, or a weak base and its conjugate acid, in order to effectively resist changes in pH. HCl is a strong acid and does not have a conjugate base, while NaCl is a salt and does not contain any acidic or basic components. Therefore, a solution composed of HCl and NaCl would not produce an effective buffer.

Question 7

An aqueous solution contains a [H₃O⁺] that is 1.0 × 10^-3 M. What is the [OH^-] of this solution? A)1.0 × 10^-14 M B)1.0 × 10^-11 M C)1.0 × 10^-3 M D)1.0 × 10¹¹ M

Accepted Answer

The balanced equation for the dissociation of H₃O⁺ is: HSO4- ⇌ H+ + SO4^2- From the given concentration of [HSO4-], we can assume that it completely dissociates in water to form H+ and SO4^2-. Therefore, at equilibrium, the [H+] will be equal to the initial concentration of [HSO4-]. pH is defined as the negative logarithm of the hydrogen ion concentration. So, pH = -log[H+] = -log[HSO4-] = -log(1.0 × 10^-3) = 3 pOH + pH = 14 pOH = 14 - pH = 14 - 3 = 11 Now, pOH = -log[OH-] -log[OH-] = 11 [OH-] = 1.0 × 10^-11 Therefore, [OH-] in the solution is 1.0 × 10^-11 M, and the [OH-] is Answer: B.

Question 8

For a healthy individual, the pH of the blood in the veins is lower than in the arteries.

Accepted Answer

The answer of For a healthy individual, the pH of...

Question 9

Which of the following is present in pure water? A)H₃O⁺ B)OH− C)H₂O D)All are present in pure water.

Accepted Answer

Pure water naturally contains H3O+ (hydronium ions), OH− (hydroxide ions), and H2O molecules. These species are in equilibrium with each other, which is a fundamental concept in the chemistry of water.

Question 10

The range of breaths per minute, also known as respiratory rate, for a normal, healthy adult is 12-20 breaths per minute. A breathing rate of higher than this is termed hyperventilation.

Accepted Answer

This is correct. Hyperventilation is defined as a breathing rate higher than the normal range of 12-20 breaths per minute.

Question 11

The following solutions are ranked from the most acidic to the most basic.
Most acidic urine (pH 5.89) intestine contents (pH 8.06) blood (pH 7.30) Most basic

Accepted Answer

The correct order from most acidic to most basic should be: urine (pH 5.89), blood (pH 7.30), intestine contents (pH 8.06).

Question 12

Adipic acid has the formula given below.  This is a polyprotic acid.

Accepted Answer

Adipic acid has two carboxylic acid groups, which can each donate a proton (H+) in solution. Therefore, it is a polyprotic acid.

Question 13

The molar concentration of H₃O⁺ in an aqueous solution would be increased by the addition of KOH.

Accepted Answer

The addition of KOH would not increase the molar concentration of H₃O⁺, as it is not an acid-base reaction involving this species.

Question 14

Both the kidneys and the carbon dioxide-carbonic acid cycle help regulate blood pH.

Accepted Answer

Both the kidneys and the carbon dioxide-carbonic acid cycle contribute to the maintenance of acid-base balance in the body, thus regulating blood pH. The kidneys can remove excess acids or bases from the blood through urine excretion, while the carbon dioxide-carbonic acid cycle helps buffer the blood by converting carbon dioxide into bicarbonate ions when the blood pH is too low.

Question 15

In converting from the pH of a solution to the corresponding H₃O⁺ concentration, the following equation should be used. [H₃O⁺] = 10^-pH

Accepted Answer

This is the correct equation for converting pH to the concentration of H₃O⁺.

Question 16

Below is the structure for the amino acid alanine. Alanine can undergo an internal acid-base reaction. In this reaction, the -NH₂ group functions as a base.

Accepted Answer

The statement is true. Alanine can undergo an internal acid-base reaction in which the -NH₂ group functions as a base.

Question 17

Nitroaniline (C₆H₆N₂O₂) is a weak base. This would indicate that the pH of a 0.010 M solution of nitroaniline will be less than 7.

Accepted Answer

A weak base like nitroaniline will have a pH greater than 7 in solution, as it partially accepts protons, increasing the hydroxide ion concentration.

Question 18

Very rapid breathing can lead to a condition know as respiratory acidosis.

Accepted Answer

Very rapid breathing leads to respiratory alkalosis, not acidosis, because it causes excessive expulsion of CO2, which decreases the acidity of the blood.

Question 19

H⁺, H₃O⁺, and OH⁺ are different ways of representing the species that causes a solution to be acidic.

Accepted Answer

The given representations seem to be a mix of symbols and numbers that do not correspond to any recognized chemical notation for acids or other species that cause solutions to be acidic. Chemical species that cause solutions to be acidic are typically represented by their chemical formulas, such as HCl for hydrochloric acid, H2SO4 for sulfuric acid, etc.

Question 20

Adipic acid has the formula given below.  Thus substance would be classified as amphiprotic.

Accepted Answer

The answer of Adipic acid has the formula given below....

Quiz 7: Acids and Bases

The following represents the structure of a hydronium ion.

The pKa of lactic acid is 3.86, an equimolar solution of lactic acid and potassium lactate will have a pH of 7.72.

The following is an accurate description of the ionization of HBr in water.

A solution is 0.10 M in ascorbic acid (Vitamin C), H2C6H6O6, and 0.10 M in sodium ascorbate, NaHC6H6O6. When base is added to the solution, H2C6H6O6 neutralizes the added base.

Consider the following reaction. CH3OH(l) + CH3OH(l) CH3O-(l) + CH3OH2+(l) This reaction could be classified as both an autoionization reaction and a proton transfer reaction.

A solution composed of HCl and NaCl would produce an effective buffer.

An aqueous solution contains a [H3O+] that is 1.0 × 10-3 M. What is the [OH-] of this solution?

For a healthy individual, the pH of the blood in the veins is lower than in the arteries.

Which of the following is present in pure water?

The range of breaths per minute, also known as respiratory rate, for a normal, healthy adult is 12-20 breaths per minute. A breathing rate of higher than this is termed hyperventilation.

The following solutions are ranked from the most acidic to the most basic. Most acidic urine (pH 5.89) intestine contents (pH 8.06) blood (pH 7.30) Most basic

Adipic acid has the formula given below. This is a polyprotic acid.

The molar concentration of H3O+ in an aqueous solution would be increased by the addition of KOH.

Both the kidneys and the carbon dioxide-carbonic acid cycle help regulate blood pH.

In converting from the pH of a solution to the corresponding H3O+ concentration, the following equation should be used. [H3O+] = 10-pH

Below is the structure for the amino acid alanine. Alanine can undergo an internal acid-base reaction. In this reaction, the -NH2 group functions as a base.

Nitroaniline (C6H6N2O2) is a weak base. This would indicate that the pH of a 0.010 M solution of nitroaniline will be less than 7.