DD Exam 4: Comprehensive Study Guide and Review
Dextrose is a neutral molecule with a higher molecular weight than sodium chloride. Will a 0.9%
aqueous solution of dextrose be hypotonic, isotonic, or hypertonic?
A. Hypotonic
B. Isotonic
C. Hypertonic - correct answer ✔✔hypotonic (a)
Osmolarity (osmoles per liter) equals molarity when the solute provides one ion or particle per
molecule.
A. True
B. False - correct answer ✔✔True (A)
Methylphenidate is an amine that is about 10% ionized (protonated) at pH 9.77. What is the
approximate pKa of methylphenidate?
A. 7.77
B. 8.77
C. 9.77
D. 10.77 - correct answer ✔✔B
Which drugs are marketed as hydrochloride salts?
A. Basic drugs
B. Neutral molecules
C. Acidic drugs - correct answer ✔✔A
Buffer capacity is usually effective over a pH range of how many pH units?
A. 2
B. 3
C. 4
,D. 1
E. only when pH=pKa - correct answer ✔✔A
What is the pKa of acetamide?
Structure: CH3CONH2
Base: Not a base (is an amide)
A. pKa about 9-10
B. pKa about 5
C. Acetamide is a neutral molecule (pKa not in range of 1 to 14) - correct answer ✔✔C
A 0.154 M solution of NaCl (MW 58.5) is isotonic. Is a 0.154 M solution of KCl (MW 74.5) also isotonic?
A. Yes
B. no - correct answer ✔✔A
Is an IV fluid containing 9 grams of sodium chloride per liter isotonic, hypotonic or hypertonic?
A. Hypotonic
B. Hypertonic
C. Isotonic - correct answer ✔✔C
In what concentration should potassium acetate and acetic acid (pKa 4.76) be added to make a solution
with a pH of 4.76?
A. Equal molar quantities of acetic acid and potassium acetate
B. Equal milligram amounts of acetic acid and potassium acetate - correct answer ✔✔A
Given the following package insert excerpt for gabapentin:
,PI says: Freely soluble in water and both basic and acidic aq solns. The LogP is -1.25 at pH7.4. pka1= 3.7
pka2= 10.7. It contains an amine and carboxylic acid in its structure.
Gabapentin forms a salt in a reaction with strong acids, and also forms a salt in a reaction with strong
bases.
A. True
B. False - correct answer ✔✔A
Which neutral drug is more likely to be dissolution rated limited, testosterone (log P = 3.32) or niacin (log
P = 0.36)?
A. testosterone
B. niacin - correct answer ✔✔A
For a buffer solution consisting of 1 L of a solution of 1 M of sodium acetate and 0.2 M of acetic acid (pKa
4.76), what is the pH of the solution?
A. 5.46
B. 4.76
C. 3.76
D. 4.06
E. 9.76 - correct answer ✔✔A
What will be the approximate pH of an acetate buffer made from 0.1 M acetic acid (pKa 4.76, MW 60)
and 0.1 M sodium acetate (MW 72)?
A. 3.6
B. 4.76
C. 5.06 - correct answer ✔✔B
This gabapentin oral solution product is probably buffered.
, Soln contains: flavor, d-xylitol, glacial acetic acid, glycerin, purified water, sodium acetate.
Glacial acetic acid and/or sodium acetate are used to adjust pH
A. True
B. False - correct answer ✔✔A
Given the sodium chloride equivalent of ephedrine sulfate as 0.23, how much sodium chloride is
equivalent to one g of ephedrine sulfate?
A. 0.9 g of NaCl
B. 3.9 g of NaCl
C. 0.23 g NaCl - correct answer ✔✔C
Which physicochemical property is most useful for determining the effect of pH on the degree of
ionization of a drug?
A. Log D
B. Log P - correct answer ✔✔A
Using Lipinski's four Rules of Five, would you expect venlafaxine pictured below to be orally effective?
LogP: 2.9
MW: 277.4
H Donors: 1
H Acceptors: 3
A. only 3 of the criteria have been met, and the drug may not be well adsorbed
B. All of the requirements have been met, and the drug is likely to be absorbed orally - correct answer
✔✔B
Given the following package insert excerpt for gabapentin:
Dextrose is a neutral molecule with a higher molecular weight than sodium chloride. Will a 0.9%
aqueous solution of dextrose be hypotonic, isotonic, or hypertonic?
A. Hypotonic
B. Isotonic
C. Hypertonic - correct answer ✔✔hypotonic (a)
Osmolarity (osmoles per liter) equals molarity when the solute provides one ion or particle per
molecule.
A. True
B. False - correct answer ✔✔True (A)
Methylphenidate is an amine that is about 10% ionized (protonated) at pH 9.77. What is the
approximate pKa of methylphenidate?
A. 7.77
B. 8.77
C. 9.77
D. 10.77 - correct answer ✔✔B
Which drugs are marketed as hydrochloride salts?
A. Basic drugs
B. Neutral molecules
C. Acidic drugs - correct answer ✔✔A
Buffer capacity is usually effective over a pH range of how many pH units?
A. 2
B. 3
C. 4
,D. 1
E. only when pH=pKa - correct answer ✔✔A
What is the pKa of acetamide?
Structure: CH3CONH2
Base: Not a base (is an amide)
A. pKa about 9-10
B. pKa about 5
C. Acetamide is a neutral molecule (pKa not in range of 1 to 14) - correct answer ✔✔C
A 0.154 M solution of NaCl (MW 58.5) is isotonic. Is a 0.154 M solution of KCl (MW 74.5) also isotonic?
A. Yes
B. no - correct answer ✔✔A
Is an IV fluid containing 9 grams of sodium chloride per liter isotonic, hypotonic or hypertonic?
A. Hypotonic
B. Hypertonic
C. Isotonic - correct answer ✔✔C
In what concentration should potassium acetate and acetic acid (pKa 4.76) be added to make a solution
with a pH of 4.76?
A. Equal molar quantities of acetic acid and potassium acetate
B. Equal milligram amounts of acetic acid and potassium acetate - correct answer ✔✔A
Given the following package insert excerpt for gabapentin:
,PI says: Freely soluble in water and both basic and acidic aq solns. The LogP is -1.25 at pH7.4. pka1= 3.7
pka2= 10.7. It contains an amine and carboxylic acid in its structure.
Gabapentin forms a salt in a reaction with strong acids, and also forms a salt in a reaction with strong
bases.
A. True
B. False - correct answer ✔✔A
Which neutral drug is more likely to be dissolution rated limited, testosterone (log P = 3.32) or niacin (log
P = 0.36)?
A. testosterone
B. niacin - correct answer ✔✔A
For a buffer solution consisting of 1 L of a solution of 1 M of sodium acetate and 0.2 M of acetic acid (pKa
4.76), what is the pH of the solution?
A. 5.46
B. 4.76
C. 3.76
D. 4.06
E. 9.76 - correct answer ✔✔A
What will be the approximate pH of an acetate buffer made from 0.1 M acetic acid (pKa 4.76, MW 60)
and 0.1 M sodium acetate (MW 72)?
A. 3.6
B. 4.76
C. 5.06 - correct answer ✔✔B
This gabapentin oral solution product is probably buffered.
, Soln contains: flavor, d-xylitol, glacial acetic acid, glycerin, purified water, sodium acetate.
Glacial acetic acid and/or sodium acetate are used to adjust pH
A. True
B. False - correct answer ✔✔A
Given the sodium chloride equivalent of ephedrine sulfate as 0.23, how much sodium chloride is
equivalent to one g of ephedrine sulfate?
A. 0.9 g of NaCl
B. 3.9 g of NaCl
C. 0.23 g NaCl - correct answer ✔✔C
Which physicochemical property is most useful for determining the effect of pH on the degree of
ionization of a drug?
A. Log D
B. Log P - correct answer ✔✔A
Using Lipinski's four Rules of Five, would you expect venlafaxine pictured below to be orally effective?
LogP: 2.9
MW: 277.4
H Donors: 1
H Acceptors: 3
A. only 3 of the criteria have been met, and the drug may not be well adsorbed
B. All of the requirements have been met, and the drug is likely to be absorbed orally - correct answer
✔✔B
Given the following package insert excerpt for gabapentin:
