Question 1

Ammonia and ammonium are both present in water at equilibrium, as shown by the following acid-base equation. What will happen if ammonium is added to a solution of ammonia and ammonium at equilibrium? NH3 + H2O  +NH4 + F1F1F1S1F1F1F10OH
Ammonia water ammonium hydroxide

Accepted Answer

A)  Nothing. 
B)  The result is not predictable. 
C)  The ammonium will bubble. 
D)  The equilibrium will shift to the right. 
E)  The equilibrium will shift to the left.

Question 2

Each circle is a sample of an aqueous acidic or basic solution. Which of the solutions contains a strong acid?

Accepted Answer

A)  
B)  
C)  
D)  
E)

Question 3

Which of the following statements does NOT describe a pH buffer?

Accepted Answer

A)  A common buffer is a solution of acetic acid and acetate. 
B)  A buffer is a weak acid and the acid's conjugate base in equal concentrations. 
C)  A buffer is a physical barrier that blocks the addition of acid or base to a solution. 
D)  A buffer is a solution that resists change of pH upon addition of small amounts of acid or base. 
E)  Phosphates, bicarbonate, and proteins are all buffering systems in the body.

Question 4

Where does digestion of proteins begin?

Accepted Answer

A)  in the mouth 
B)  in the esophagus 
C)  in the stomach 
D)  in the small intestine 
E)  in the large intestine

Question 5

The buffering system of the blood is shown below. Which of the following equations represents the reaction that occurs when hydroxide is added to this buffer?

Accepted Answer

A)  CO2 + F1F1F1S1F1F1F10OH → CO32F1F1F1S1F1F1F10 + H+ 
B)  H2CO3 + F1F1F1S1F1F1F10OH → HCO3F1F1F1S1F1F1F10 + H2O 
C)  HCO3F1F1F1S1F1F1F10 + F1F1F1S1F1F1F10OH → CO32F1F1F1S1F1F1F10 + H2O 
D)  HCO3F1F1F1S1F1F1F10 + F1F1F1S1F1F1F10OH → CO2 + H2O2 
E)  H3O+ + F1F1F1S1F1F1F10OH → 2 H2O

Question 6

Which of the following statements best describes the behavior of water in the acid-base reaction between dopamine and water?

Accepted Answer

A)  Water is the acid. 
B)  Water is the base. 
C)  Water is the conjugate acid. 
D)  Water is the conjugate base. 
E)  Water is both an acid and a base.

Question 7

Which of the following statements about acids is NOT true?

Accepted Answer

A)  An example of an acid is HBr. 
B)  An acid increases the concentration of hydroxide in solution. 
C)  An acid increases the concentration of protons in solution. 
D)  An acid increases the concentration of hydronium in solution. 
E)  An acid is a proton donor.

Question 8

The following reaction is a reversible reaction. Which of the following statements best describes what it means for this reaction to be reversible?

Accepted Answer

A)  This reaction only occurs in the reverse direction as written above. 
B)  All of the reactant molecules react to make product and then all of the product molecules react to make reactants again. 
C)  Forward and reverse reactions proceed at the same rate. 
D)  Forward and reverse reactions occur simultaneously. 
E)  The rate of the reverse reaction is must faster than the rate of the forward reaction.

Question 9

Methylamide (CH3CONH2) has a Ka of 1 F1F1F1S1F1F1F10 10-16. What is the pKa of methylamide?

Accepted Answer

A)  "F1F1F1S1F1F1F1016" 
B)  '0" 
C)  "16" 
D)  "1 F1F1F1S1F1F1F10 10-16" 
E)  "F1F1F1S1F1F1F101 F1F1F1S1F1F1F10 10-16"

Question 10

A sample of gastric juice has a pH of 1.20. What is the concentration of hydroxide in this sample?

Accepted Answer

A)  1.6 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1013 M 
B)  6.3 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F102 M 
C)  1.0 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F107 M 
D)  6.3 F1F1F1S1F1F1F10 1012 M 
E)  6.3 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1016 M

Question 11

The boxed species in the following reaction is

Accepted Answer

A)   hydroxide. 
B)  hydronium. 
C)  a proton. 
D)  the acid. 
E)  the conjugate base.

Question 12

When an acid is dissolved in water, it reacts to give _________ and ________.

Accepted Answer

A)  hydroxide; hydronium 
B)  hydronium; the conjugate acid 
C)  hydroxide; the conjugate acid 
D)  hydronium; the conjugate base 
E)  hydroxide; the conjugate base

Question 13

What happens to pH when the buffer capacity of a solution is exceeded?

Accepted Answer

A)  The pH increases. 
B)  The pH decreases. 
C)  The solution will become unstable. 
D)  The pH will either increase or decrease, depending on whether acid or base is added to the solution. 
E)  The pH will not be changed.

Question 14

A blood sample has a pH of 7.42. What is the concentration of hydronium in the sample?

Accepted Answer

A)  "0.87 M" 
B)  "2.6 F1F1F1S1F1F1F10 107 M" 
C)  "F1F1F1S1F1F1F102.6 F1F1F1S1F1F1F10 107 M" 
D)  "3.8 F1F1F1S1F1F1F10 108 M" 
E)  "3.8 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F108 M"

Question 15

Gastric juice is the most acidic fluid in the body. Why is gastric juice so acidic?

Accepted Answer

A)  to convert inactive proteins to active ones 
B)  to kill bacteria 
C)  to denature proteins 
D)  to break down food 
E)  All of the above

Question 16

What is the concentration of H3O+ and -OH in pure water at room temperature?

Accepted Answer

A)  1.0 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1014 M 
B)  1.0 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F107 M 
C)  1.0 M 
D)  1.0 F1F1F1S1F1F1F10 107 M 
E)  1.0 F1F1F1S1F1F1F10 1014 M

Question 17

Which of the following statements best describes the purpose of insulin in the body?

Accepted Answer

A)  Insulin transports carbohydrates through the bloodstream. 
B)  Insulin controls glucose concentration in the blood. 
C)  Insulin breaks down sugars in the body. 
D)  Insulin protects sugars from being broken down by enzymes. 
E)  Insulin controls protein metabolism.

Question 18

Which of the following statements best describes what it means for the acid-base reaction between acetic acid and water to be in equilibrium?

Accepted Answer

A)  The mass of acetic acid and acetate is equal. 
B)  The number of moles of acetate equals the number of moles of acetic acid. 
C)  The number of moles of hydronium equals the number of moles of water. 
D)  The forward and reverse reactions proceed at the same rate. 
E)  The reaction is balanced.

Question 19

Which of the following statements does NOT correctly describe buffer capacity?

Accepted Answer

A)  Buffer capacity is determined only by the identity of the buffer. 
B)  The addition of amounts of acid or base exceeding the buffer capacity will change the pH of the solution. 
C)  The higher the concentration of weak acid and conjugate base in solution, the higher the buffer capacity. 
D)  The greatest amount of acid or base that a buffer can accept while maintaining pH is called the buffer capacity. 
E)  Once the buffer capacity is exceeded in cells, key functions of the body can be disrupted.

Question 20

The boxed species in the following reaction is

Accepted Answer

A)  hydroxide. 
B)  hydronium. 
C)  a proton. 
D)  the acid. 
E)  the base.

Exam 9: Acids and Bases

Ammonia and ammonium are both present in water at equilibrium, as shown by the following acid-base equation. What will happen if ammonium is added to a solution of ammonia and ammonium at equilibrium? NH₃ + H₂O ⁺NH₄ + ^OH Ammonia water ammonium hydroxide

Each circle is a sample of an aqueous acidic or basic solution. Which of the solutions contains a strong acid?

Which of the following statements does NOT describe a pH buffer?

Where does digestion of proteins begin?

The buffering system of the blood is shown below. Which of the following equations represents the reaction that occurs when hydroxide is added to this buffer?

Which of the following statements best describes the behavior of water in the acid-base reaction between dopamine and water?

Which of the following statements about acids is NOT true?

The following reaction is a reversible reaction. Which of the following statements best describes what it means for this reaction to be reversible?

Methylamide (CH₃CONH₂) has a K_a of 1  10^-16. What is the pK_a of methylamide?

A sample of gastric juice has a pH of 1.20. What is the concentration of hydroxide in this sample?

The boxed species in the following reaction is

When an acid is dissolved in water, it reacts to give _ and .

What happens to pH when the buffer capacity of a solution is exceeded?

A blood sample has a pH of 7.42. What is the concentration of hydronium in the sample?

Gastric juice is the most acidic fluid in the body. Why is gastric juice so acidic?

What is the concentration of H₃O⁺ and ^-OH in pure water at room temperature?

Which of the following statements best describes the purpose of insulin in the body?

Which of the following statements best describes what it means for the acid-base reaction between acetic acid and water to be in equilibrium?

Which of the following statements does NOT correctly describe buffer capacity?

The boxed species in the following reaction is

Exam 9: Acids and Bases

Ammonia and ammonium are both present in water at equilibrium, as shown by the following acid-base equation. What will happen if ammonium is added to a solution of ammonia and ammonium at equilibrium? NH3 + H2O +NH4 + OH Ammonia water ammonium hydroxide

Each circle is a sample of an aqueous acidic or basic solution. Which of the solutions contains a strong acid?

Which of the following statements does NOT describe a pH buffer?

Where does digestion of proteins begin?

The buffering system of the blood is shown below. Which of the following equations represents the reaction that occurs when hydroxide is added to this buffer?

Which of the following statements best describes the behavior of water in the acid-base reaction between dopamine and water?

Which of the following statements about acids is NOT true?

The following reaction is a reversible reaction. Which of the following statements best describes what it means for this reaction to be reversible?

Methylamide (CH3CONH2) has a Ka of 1  10-16. What is the pKa of methylamide?

A sample of gastric juice has a pH of 1.20. What is the concentration of hydroxide in this sample?

The boxed species in the following reaction is

When an acid is dissolved in water, it reacts to give _________ and ________.

What happens to pH when the buffer capacity of a solution is exceeded?

A blood sample has a pH of 7.42. What is the concentration of hydronium in the sample?

Gastric juice is the most acidic fluid in the body. Why is gastric juice so acidic?

What is the concentration of H3O+ and -OH in pure water at room temperature?

Which of the following statements best describes the purpose of insulin in the body?

Which of the following statements best describes what it means for the acid-base reaction between acetic acid and water to be in equilibrium?

Which of the following statements does NOT correctly describe buffer capacity?

The boxed species in the following reaction is

Ammonia and ammonium are both present in water at equilibrium, as shown by the following acid-base equation. What will happen if ammonium is added to a solution of ammonia and ammonium at equilibrium? NH₃ + H₂O ⁺NH₄ + ^OH Ammonia water ammonium hydroxide

Methylamide (CH₃CONH₂) has a K_a of 1  10^-16. What is the pK_a of methylamide?

When an acid is dissolved in water, it reacts to give _ and .

What is the concentration of H₃O⁺ and ^-OH in pure water at room temperature?