PHA 317 Final Exam Questions
and Answers 100% Pass
What is the pH of a buffer containing 0.1 -M acetic acid (pKa 4.8) and 0.08 M
sodium acetate? - CORRECT ANSWER-4.7
What percentage of an acidic drug indomethacine (pKa 4.5) exist in the original
unionized form in an intestinal tract buffered at pH 8.0? - CORRECT ANSWER-
0.03%
What molar ratio of sodium acetate and acetic acid (pKa 4.76) should you use to
prepare an acetate buffer of pH 5? - CORRECT ANSWER-1.74:1
Stronger bases, such as guanethidine (pKa > 11) are ionized throughout the GI
tract and tend to be well-absorbed throughtout the GI tract. - CORRECT
ANSWER-false
The biological membrane is covered on both side by lipid layers which are
interrupted by water filled pores. Which of the following statements is correct? -
CORRECT ANSWER-The radius of the aqueous pores on biomembrane is
approximately 4 Angstrom, therefore, any hydrophilic drug smaller than 4
Angstrom can get transported through it easily.
,Strong bases, which are those with pKa values between 5 and 11, show pH-
dependent absorption. - CORRECT ANSWER-true
Digestion and absorption of foodstuff occur separately at different times in the
small intestine - CORRECT ANSWER-false
The greater the pKa value, the stronger the acid would be. - CORRECT
ANSWER-false
Below are some statements about the concept of equilibrium in pharmaceutics:
i. a condition at which all acting influences are canceled by others, resulting in a
stable, balanced, or unchanged system
ii. the state of a chemical reaction in which its forward and reverse reactions occur
at equal rates so that the concentration of the reactants and products remain
unchanged with time
iii. a condition at which no change in concentrations of either reactant or product
is observed because they stop reacting with each other
iv. the state of a reversible chemical reaction in which the forward and reverse
reactions occur at equal rates so that there are no further changes in the
concentrations of the reactants and products - CORRECT ANSWER-only i, ii,
and iv are correct
, The transport of weak acidic drugs across gastrointestinal membrane is influenced
by pH only if their pKa values are within the range of 3-7 - CORRECT
ANSWER-true
Stronger bases, such as guanethidine (pKa > 11) are ionized throughout the GI
tract and tend to be poorly absorbed - CORRECT ANSWER-true
The lower the pKa value for an acid, the greater hydronium ion concentration it
would produce on being added to water - CORRECT ANSWER-true
Generally, absorption or transport of a drug in ionized form through GI
membrane would be more than its unionized form - CORRECT ANSWER-false
The polar surface area is defined as the sum of the Van der Waals surface areas for
the polar ataoms, oxygens, nitrogens, and attached hydrogen atom (or the number
of H-bonded donors and H-bond acceptors) - CORRECT ANSWER-true
How are lipids arranged on both side of a biomembrane? - CORRECT ANSWER-
perpendicularly
The pH range of duodenum is: - CORRECT ANSWER-5 to 7
The brush border consists of a 3 mm thick uniform coating of
mucopolysaccharide which is found lining the internal wall of stomach only -
CORRECT ANSWER-false
Equilibrium is involved in the following processes playing an important role in
pharmaceutics:
and Answers 100% Pass
What is the pH of a buffer containing 0.1 -M acetic acid (pKa 4.8) and 0.08 M
sodium acetate? - CORRECT ANSWER-4.7
What percentage of an acidic drug indomethacine (pKa 4.5) exist in the original
unionized form in an intestinal tract buffered at pH 8.0? - CORRECT ANSWER-
0.03%
What molar ratio of sodium acetate and acetic acid (pKa 4.76) should you use to
prepare an acetate buffer of pH 5? - CORRECT ANSWER-1.74:1
Stronger bases, such as guanethidine (pKa > 11) are ionized throughout the GI
tract and tend to be well-absorbed throughtout the GI tract. - CORRECT
ANSWER-false
The biological membrane is covered on both side by lipid layers which are
interrupted by water filled pores. Which of the following statements is correct? -
CORRECT ANSWER-The radius of the aqueous pores on biomembrane is
approximately 4 Angstrom, therefore, any hydrophilic drug smaller than 4
Angstrom can get transported through it easily.
,Strong bases, which are those with pKa values between 5 and 11, show pH-
dependent absorption. - CORRECT ANSWER-true
Digestion and absorption of foodstuff occur separately at different times in the
small intestine - CORRECT ANSWER-false
The greater the pKa value, the stronger the acid would be. - CORRECT
ANSWER-false
Below are some statements about the concept of equilibrium in pharmaceutics:
i. a condition at which all acting influences are canceled by others, resulting in a
stable, balanced, or unchanged system
ii. the state of a chemical reaction in which its forward and reverse reactions occur
at equal rates so that the concentration of the reactants and products remain
unchanged with time
iii. a condition at which no change in concentrations of either reactant or product
is observed because they stop reacting with each other
iv. the state of a reversible chemical reaction in which the forward and reverse
reactions occur at equal rates so that there are no further changes in the
concentrations of the reactants and products - CORRECT ANSWER-only i, ii,
and iv are correct
, The transport of weak acidic drugs across gastrointestinal membrane is influenced
by pH only if their pKa values are within the range of 3-7 - CORRECT
ANSWER-true
Stronger bases, such as guanethidine (pKa > 11) are ionized throughout the GI
tract and tend to be poorly absorbed - CORRECT ANSWER-true
The lower the pKa value for an acid, the greater hydronium ion concentration it
would produce on being added to water - CORRECT ANSWER-true
Generally, absorption or transport of a drug in ionized form through GI
membrane would be more than its unionized form - CORRECT ANSWER-false
The polar surface area is defined as the sum of the Van der Waals surface areas for
the polar ataoms, oxygens, nitrogens, and attached hydrogen atom (or the number
of H-bonded donors and H-bond acceptors) - CORRECT ANSWER-true
How are lipids arranged on both side of a biomembrane? - CORRECT ANSWER-
perpendicularly
The pH range of duodenum is: - CORRECT ANSWER-5 to 7
The brush border consists of a 3 mm thick uniform coating of
mucopolysaccharide which is found lining the internal wall of stomach only -
CORRECT ANSWER-false
Equilibrium is involved in the following processes playing an important role in
pharmaceutics:
