Questions:

1. A hydrogen bond can be formed between
  1. A hydroxyl group and a saturated hydrocarbon like methane
  2. A hydroxyl group and a nitrogen atom in an amide bond (FIG. 5.2)
  3. An ammonium ion and a saturated hydrocarbon like methane
  4. An ammonium ion and a phosphate atom in phosphate
  5. A sodium ion and a chloride ion
2. Water molecules dissociate producing hydrogen ions (H+), and hydroxide ions (OH-). Regarding the ion product of water, all of the following statements are true EXCEPT:
  1. At equilibrium, the product of the concentrations of the dissociated ions divided by the concentration of the undissociated water is a constant, K
  2. In an aqueous solution the concentrations of hydrogen ions and hydroxide are inversely proportional
  3. Because the extent of dissociation is very small, the concentration of pure water remains essentially at 55.5 M
  4. Kw is a constant representing the ion product of water and is equivalent to = 1 x 10-14.
  5. If H+ is added to an aqueous solution, OH- increases proportionately
3. When utilizing the ion product of water (Kw = 1 x 10-14), an increase in [H+] would cause a(n) _____in [OH-]
  1. Increase
  2. Decrease
  3. No change
  4. Can not be determined
4. The pH of a solution is defined as a measure of its hydrogen ion concentration. Which of the following correctly defines the relationship between the pH and the hydrogen ion concentration of a solution?
  1. When the pH of a solution changes by a factor of 2, the hydrogen ion concentration changes by 0.3
  2. When the pH of a solution changes by 0.6, the hydrogen ion concentration changes by a factor of 3
  3. Changing the pH of a solution does not effect the hydrogen ion concentration in any predictable way
  4. When the pH of a solution changes by 0.3, the hydrogen ion concentration changes by a factor of 2
  5. When the pH of a solution changes by a factor of 3, the hydrogen ion concentration changes by 0.6
5. The pH of a blood sample with an [H+] of 40 x 10-9 Eq/L is
  1. 6.4
  2. 5.3
  3. 7.4
  4. 8.4
  5. 4.9
6. According to the Lowry-Bronsted definition of acids and bases:
  1. The term acid refers to any substance that is capable or releasing a proton
  2. The term base is used to describe any substance that is capable of binding a proton in aqueous solution
  3. The term acid is any substance that is capable of accepting a proton
  4. The term base is used to describe any substance that is capable of releasing a proton in aqueous solution
  5. A and B are correct
7. The following acids are produced by the body except;
  1. Carbonic acid
  2. Sulfuric acid
  3. Ketone bodies
  4. Acetylsalicylic acid
  5. Lactic Acid
8. Which of the following statements is true based on your understanding of the difference between a strong acid and a weak acid.
  1. Strong acids in aqueous solution dissociate completely into anions and protons
  2. Both strong and weak acids in aqueous solution dissociate only to a limited extent
  3. Weak acids in aqueous solution dissociate completely into cations and protons
  4. Weak acids in aqueous solution dissociate completely into anions and protons
  5. Strong acids in aqueous solution dissociate only into cations and protons
9. Many of the properties of strong and weak acids are different. All of the following a properties of weak acids EXCEPT:
  1. Dissociate only slightly when added to water
  2. Dissociate completely if the pH is raised
  3. Have a pKa
  4. Can serve as buffers
  5. Dissociate completely at any pH
10. Regarding the Henderson-Hasselbalch equation, all of the following statements are true EXCEPT:
  1. The Henderson-Hasselbalch equation is derived from the formula for the dissociation constant of a weak acid, expressing it in logarithmic form
  2. The Henderson-Hasselbalch equation relates the pH to the pKa and the log of the ratio of dissociated to undissociated acid
  3. The Henderson-Hasselbalch equation is useful for calculating the molar ratio of base to acid to achieve a given pH
  4. The Henderson-Hasselbalch equation can be used to calculate the pKa for a weak acid, if the pH and the ratio of base to acid can be determined
  5. The Henderson-Hasselbalch equation is most useful for determining the molar amount of strong acid in solution
11. The pH of a buffer in the blood can be determined by
  1. pH = pKa + log [acid]/[base]
  2. pH = pKa + log [base]/[acid]
  3. pH = 7.0 + log [base]/[acid]
  4. pH = pKa – log [base]/[acid]
  5. pH = 7.4 - log [base]/[acid]
12. Which two factors determine the effectiveness of a buffer?
  1. The pKa of the buffer relative to the pH of the solution and the concentration buffer
  2. The pKa of the buffer relative to the pH of the solution and the temperature of the solution
  3. The pH and temperature of the solution
  4. The concentration of the buffer and the pressure of the solution
  5. The ratio of acid to base in the solution and the concentration of strong acid
13. All of the following are true of buffers EXCEPT:
  1. Consist of a strong acid and its conjugate base
  2. Work best within one pH unit of the pKa
  3. Effectiveness is relative to the pH of solution and concentration of buffer
  4. Buffered solutions resist changes in pH when acid or base is added to solution
14. Why is it imperative that the pH of most tissues and cells be maintained within a narrow range? You know that changing the pH will change the conformation of proteins and this
  1. would alter the solubility of some enzymes
  2. would change the rate of enzymatic reactions
  3. can alter the structure of the cell
  4. can alter the functions of the cell
  5. All of the above are correct
15. The normal pH range of arterial blood is 7.37 to 7.43. Which two buffing systems are responsible for maintaining blood pH?
  1. Bicarbonate and hemoglobin
  2. Bicarbonate and monohydrogen phosphate
  3. Monohydrogen phosphate and dihydrogen phosphate
  4. Hemoglobin and monohydrogen phosphate
  5. Bicarbonate and carbonic acid
16. The pH of the blood plasma is precisely maintained at a value near 7.4. What is the name of the disorder and the respiratory compensation when the blood pH rises to 7.5 as a result of a problem with metabolism?
  1. The condition is known as metabolic acidosis and the rate and depth of breathing will decrease
  2. The condition is known as metabolic alkalosis and the rate and depth of breathing will decrease
  3. The condition is called metabolic acidosis and the rate and depth of breathing will increase
  4. The condition is called metabolic alkalosis and the rate and depth of breathing will increase
  5. The condition is called metabolic acidosis and the rate of breathing will increase, while the depth of breathing will decrease
17. At pH 7.4, some of the H2CO3 produced from a reaction catalyzed by carbonic anhydrase immediately dissociates into
  1. H+, CO2
  2. H+, HCO3-
  3. OH-, CO2
  4. OH-, HCO3-
18. Regarding the dissociation of ammonium ion, if the pKa = 9.3, what form would be predominantly found at pH = 7.4?
  1. Carbonic acid
  2. Ammonium ion
  3. Lactic acid, pKa
  4. Phosphoric acid
  5. Ammonia
19. The dissociation of ammonium ion and its predominant form at pH 7:
  1. NH4+ = H+ + NH3, NH3
  2. NH4+ = H+ + NH3, NH4+
  3. NH3 = H+ + NH4+, NH4+
  4. NH3 = H+ + NH4+, NH3
20. Di Abietes has insulin dependent diabetes mellitus (type 1). When she neglects to take her insulin, she remains in a condition similar to a fasting state. Which of the following correctly identifies the laboratory findings you would expect to see when Di arrives at your emergency room?
  1. Serum glucose is low, ketone bodies levels are high and glucagon is decreased
  2. Serum glucose is high, ketone bodies levels are high and glucagon is elevated
  3. Serum glucose is low, ketone bodies levels are low and glucagon is decreased
  4. Serum glucose is low, ketone bodies levels are high and glucagon is elevated
  5. Serum glucose is high, ketone bodies levels are low and glucagon is elevated
21. Di Abietes’ suffers from Type 1 diabetes and without insulin she may present with the following signs/symptoms of poor management EXCEPT
  1. Hyperglycemic and acetone breath
  2. Euglycemic and ketoacidotic
  3. Hyperglycemic and deep/rapid breathing
  4. Osmotic diuresis
  5. Hyperglycemic coma
22. Ketoacidosis refers to the metabolic acidosis caused by the overproduction of ketoacids. The classic form of ketoacidosis is uncontrolled diabetes mellitus. All of the following would occur in a patient suffering from a diabetes-induced metabolic acidosis (diabetic ketoacidosis) EXCEPT:
  1. Deep, rapid breathing causes a decrease in the partial pressure of carbon dioxide (PaCO2) in the blood
  2. The removal of carbon dioxide through deep, rapid breathing results in a rise in the blood pH
  3. When endogenous (metabolic) acid production rises sharply, net acid excretion (by the kidney) cannot keep pace and the bicarbonate lost in buffering is not replaced causing plasma HCO3- levels to fall
  4. Serum bicarbonate levels will slowly decrease after the administration of an insulin injection
  5. The fall in insulin causes fat cells to liberate fatty acids, which flood the hepatocytes
23. Di Abietes’s ketoacidosis (metabolic acidosis) impacted both the blood CO2 and bicarbonate concentration by:
  1. Increased PaCO2, decreased HCO3-
  2. Decreased PaCO2, increased HCO3-
  3. Increased PaCO2, increased HCO3-
  4. Decreased PaCO2, decreased HCO3-
24. When reviewing the lab work of a patient, at what level of fasting plasma glucose would you begin to suspect diabetes?
  1. > 100 mg/dL
  2. > 126 mg/dL
  3. > 80 mg/dL
  4. > 200 mg/dL
  5. > 160 mg/dL
25. At what random plasma (casual) glucose level, should a provider have a high index of suspicion that one may have diabetes
  1. 110-126 mg/dl
  2. <110 mg/dl
  3. 200 mg/dl or higher
  4. 80-200 mg/dl
  5. 1 X 10 14 M
26. The pKa for acetylsalicylic acid to acetylsalicylate is 3.5. At a normal stomach pH of 1, you would expect acetylsalicylic acid to be the predominate form. What would you expect to happen if the pH in the stomach began to increase?
  1. The concentration of acetylsalicylic acid would decrease and the concentration of acetylsalicylate would increase
  2. The concentration of acetylsalicylic acid would increase and the concentration of acetylsalicylate would increase
  3. The concentration of acetylsalicylic acid would decrease and the concentration of acetylsalicylate would decrease
  4. The concentration of acetylsalicylic acid would increase and the concentration of acetylsalicylate would decrease
  5. The ratio of acetylsalicylic acid to acetylsalicylate would remain the same
27. A patient is asked to breathe into and out of a brown paper bag. Rebreathing from the bag:
  1. Lowers alveolar and arterial PCO2, lowering blood pH
  2. Raises alveolar PCO2 and lowers arterial PCO2, raising blood pH
  3. Takes the patient’s mind off their anxiety so they can relax, ultimately lowering blood pH
  4. Raises both alveolar and arterial PCO2, lowering the blood pH
  5. Raises both alveolar and arterial PCO2, raising the blood pH
28. Percy Veere presents hyperventilating, causing a decreased alveolar PCO2 resulting into a decrease in blood PCO2 (respiratory alkalosis). The station nurse asked him to breath into a paper bag which caused his blood PCO2 and pH respectively
  1. Increase PCO2, raise pH
  2. Decrease PCO2, raise pH
  3. Increase PCO2, lower pH
  4. Decrease PCO2, lower pH
29. The pH of the patient’s blood is 7.7.  The patient is alkalotic and her ratio of bicarbonate to carbonic acid is? (Hint, use 6.1 for pKa.)
  1. 10 to 1
  2. 20 to 1
  3. 30 to 1
  4. 40 to 1
  5. 50 to 1
30. The pH of the patient’s blood is 7.1.  The patient is acidotic and her ratio of bicarbonate to carbonic acid is? (Hint, use 6.1 for pKa.)
  1. 10 to 1
  2. 20 to 1
  3. 30 to 1
  4. 40 to 1
  5. 50 to 1
31. The HPO4=/H2PO4-buffer system has a pKa of 6.8 .  What is the ratio of monohydrogen phosphate to dihydrogen phosphate in the urine at pH = 4.8?
  1. 100 to 1
  2. 10 to 1
  3. 1 to 1
  4. 1 to 10
  5. 1 to 100
32. If the hydrogen ion concentration of a solution changes from 1 X 10-6 to 1 X 10-7, then the hydroxide ion concentration would change from
  1. 1 X 10-6 to 1 X 10-7
  2. 1 X 10-6 to 1 X 10-8
  3. 1 X 10-8 to 1 X 10-7
  4. 1 X 10-6 to 1 X 10-6
  5. 1 X 10-6 to 1 X 10-7.4
33. If the hydrogen ion concentration of a solution is 5 X 10-6 , then the hydroxide ion concentration is?
  1. 1 X 10-6
  2. 2 X 10-7
  3. 1 X 10-8
  4. 2 X 10-8
  5. 2 X 10-9
34. The pH of a urine sample with an [H+] of 160 x 10-9 Eq/L is? (Hint! The log of 1.6 is approximately 0.2)
  1. 6.8
  2. 5.3
  3. 7.4
  4. 8.4
  5. 4.9
35. The pKa for the following biological acids are:
  • Ammonium ion = 9.2
  • Acetoacetic acid = 3.6
  • Pyruvic acid = 3.4
  • Lactic acid = 3.7
Which forms of the acids or anions are NOT present at pH = 7.4?
  1. Lactate and Pyruvate
  2. Acetoacetate and Ammonium ion
  3. Pyruvate and Acetoacetate
  4. Ammonia and Pyruvic acid
  5. Lactate and Acetoacetate
36. The pKa for acetylsalicylic acid to acetylsalicylate is 3.5. If the pH of the solution is 6.5, What is the ratio of acetylsalicylate to acetylsalicylic acid?
  1. 316 to 1
  2. 7943 to 1
  3. 100 to 1
  4. 1,000 to 1
  5. 10,000 to 1

Answers:

1. Answer: B. Chapter 4, Objective 1: Recognize a hydrogen bond and atoms or groups of atoms that can take part in forming a hydrogen bond. Back to question 1.
2. Answer: E. Chapter 4, Objective 2: Define the ion product for water! Given any hydroxide ion concentration, determine the hydrogen ion concentration and vice versa. Back to question 2.
3. Answer: B. Chapter 4, Objective 2: Define the ion product for water! Given any hydroxide ion concentration, determine the hydrogen ion concentration and vice versa. Back to question 3.
4. Answer: D. Chapter 4, Objective 3: Define pH. Define pH. Given any hydrogen ion concentration, determine the pH and vice versa. Back to question 4.
5. Answer: C. Chapter 4, Objective 3: Define pH. Given any hydrogen ion concentration, determine the pH and vice versa. Back to question 5.
6. Answer: E. Chapter 4, Objective 4: Define an acid and a base. Back to question 6.
7. Answer: D. Chapter 4, Objective 5: Recognize the acids produced by the body during metabolism and be able to state the predominant form at pH = 7.4 (ic or ate, ammonium or ammonia). Back to question 7.
8. Answer: A. Chapter 4, Objective 6: What is the difference between a strong acid and a weak acid? Can a strong acid serve as a buffer? Back to question 8.
9. Answer: E. Chapter 4, Objective 6: What is the difference between a strong acid and a weak acid? Can a strong acid serve as a buffer? Back to question 9.
10. Answer: E. Chapter 4, Objective 7: Given a weak acid, be able to draw the equation for its dissociation and label the conjugate base (salt of the acid). Be able to define the Ka for the acid. Be able to write the Henderson-Hasselbalch equation for acid. Back to question 10.
11. Answer: B. Chapter 4, Objective 7: Given a weak acid, be able to draw the equation for its dissociation and label the conjugate base (salt of the acid). Be able to define the Ka for the acid. Be able to write the Henderson-Hasselbalch equation for acid. Back to question 11.
12. Answer: A. Chapter 4, Objective 8: Define the term buffer! Name two factors that determine the effectiveness of the buffer! At what pH are buffers most effective? Back to question 12.
13. Answer: A. Chapter 4, Objective 8: Define the term buffer! Name two factors that determine the effectiveness of the buffer! At what pH are buffers most effective? Back to question 13.
14. Answer: E. Chapter 4, Objective 9: What is the most important reason for maintaining a physiological pH? Back to question 14.
15. Answer: A. Chapter 4, Objective 10: What are the two most important buffers in blood? Back to question 15.
16. Answer: B. Chapter 4, Objective 11: Be able to draw the equations that show how the bicarbonate buffer system works in blood. What is the respiratory compensation when the blood pH drops to 7.3? What is the respiratory compensation when the blood pH rises to 7.5? Back to question 16.
17. Answer: B. Chapter 4, Objective 11: Be able to draw the equations that show how the bicarbonate buffer system works in blood. What is the respiratory compensation when the blood pH drops to 7.3? What is the respiratory compensation when the blood pH rises to 7.5? Back to question 17.
18. Answer: B. Chapter 4, Objective 12: Draw the dissociation of ammonium ion, If the pKa = 9.3, what form is found at pH = 7? Back to question 18.
19. Answer: B. Chapter 4, Objective 12: Draw the dissociation of ammonium ion, If the pKa = 9.3, what form is found at pH = 7? Back to question 19.
20. Answer: B. Chapter 4, Objectives 13: Regarding Di Abietes: Define Type I diabetes. Without insulin, what happens to the blood glucagon concentration (not really discussed until chapter 24)? What happens to her blood glucose and ketone body levels (concentration)? Back to question 20.
21. Answer: B. Chapter 4, Objectives 13: Regarding Di Abietes: Define Type I diabetes. Without insulin, what happens to the blood glucagon concentration? What happens to her blood glucose and ketone body levels (concentration)? Back to question 21.
22. Answer: D. Chapter 4, Objective 14: Regarding the Di Beatty Case: Explain why an increase in a metabolic acid would cause the changes seen in PaCO2 and serum bicarbonate. What would happen to the concentration of CO2 and serum bicarbonate after the insulin injection? Back to question 22.
23. Answer: D. Chapter 4, Objective 14: Regarding the Di Beatty Case: Explain why an increase in a metabolic acid would cause the changes seen in PaCO2 and serum bicarbonate. What would happen to the concentration of CO2 and serum bicarbonate after the insulin injection? Back to question 23.
24. Answer: B. Chapter 4, Objective 15: Regarding any person suspected of having diabetes: what level of fasting plasma glucose or level of random plasma glucose would you expect to measure? Back to question 24.
25. Answer: C. Chapter 4, Objective 15: Regarding any person suspected of having diabetes: what level of fasting plasma glucose or level of random plasma glucose would you expect to measure? Back to question 25.
26. Answer: A. Chapter 4, Objective 16: Concerning Dennis Veere: If the pKa for acetylsalicylic acid to acetylsalicylate is 3.5, is aspirin a weak or strong acid? Which form is predominant in the stomach at a pH of 1? Which form is prevalent in the blood? Prove it using the Henderson-Hasselbalch equation. Back to question 26.
27. Answer: D. Chapter 4, Objective 17: Regarding Percy Veere: Using the Henderson-Hasselbalch equation, explain the effect of breathing into a paper bag upon blood pH. Back to question 27.
28. Answer: C. Chapter 4, Objective 17: Regarding Percy Veere: Using the Henderson-Hasselbalch equation, explain the effect of breathing into a paper bag upon blood pH. Back to question 28.
29. Answer: D.  Chapter 4, Objective 11: Be able to draw the equations that show how the bicarbonate buffer system works in blood! What is the respiratory compensation when the blood pH drops to 7.3? What is the respiratory compensation when the blood pH rises to 7.5?  Hint: pH = pKa + Log [salt/acid]: 7.7 = 6.1 + Log [salt/acid]; 1.6 = Log [salt/acid]; [salt/acid] = 40 Back to question 29.
30. Answer: A.  Chapter 4, Objective 11: Be able to draw the equations that show how the bicarbonate buffer system works in blood! What is the respiratory compensation when the blood pH drops to 7.3? What is the respiratory compensation when the blood pH rises to 7.5?  Hint: pH = pKa + Log [salt/acid]: 7.1 = 6.1 + Log [salt/acid]; 1.0 = Log [salt/acid]; [salt/acid] = 10 Back to question 30.
31. Answer: E.  Chapter 4, Objective 16: Concerning Dennis Veere: If the pKa for acetylsalicylic acid to acetylsalicylate is 3.5, is aspirin a weak or strong acid? Which form is prevalent in the stomach at a pH of 1? Which form is prevalent in blood? Prove it using the Henderson-Hasselbalch equation.  Hint: pH = pKa + Log [salt/acid]: 4.8 = 6.8 + Log [salt/acid]; -2 = Log [salt/acid], 2 = Log [acid/ salt]; [acid/ salt] = 100: [salt/acid] = 1/100 Back to question 31.
32. Answer: C. Chapter 4, Objective 2: Define the ion product for water! Given any hydroxide ion concentration, determine the hydrogen ion concentration and vice versa. Back to question 32.
33. Answer: E. Chapter 4, Objective 2: Define the ion product for water! Given any hydroxide ion concentration, determine the hydrogen ion concentration and vice versa. Back to question 33.
34. Answer: A. Chapter 4, Objective 3: Define pH. Given any hydrogen ion concentration, determine the pH and vice versa. Back to question 34.
35. Answer: D. Chapter 4, Objective 5: Recognize the acids produced by the body during metabolism and be able to state the predominant form at pH = 7.4 (ic or ate, ammonium or ammonia). Back to question 35.
36. Answer: D. Chapter 4, Objective 16: Concerning Dennis Veere: If the pKa for acetylsalicylic acid to acetylsalicylate is 3.5, is aspirin a weak or strong acid? Which form is predominant in the stomach at a pH of 1? Which form is prevalent in the blood? Prove it using the Henderson-Hasselbalch equation. Back to question 36.