Final Exam Review - Exam 2

Question 1

1. Most drugs are:
A. Strong electrolytes
B. Weak electrolytes
C. Non-electrolytes
D. None of the above

Answer 1

B. Weak electrolytes

Question 2

2. When 100 mL of methanol is mixed with 100 mL of ethanol, the final volume of the solution is 170 mL or 200 mL:
A. Ideal solution: 170 mL
B. Real solution: 170 mL
C. Ideal solution: 200 mL
D. Real solution: 200 mL
E. None of the above

Answer 2

C. Ideal solution: 200 mL

Question 3

3. H2O can act as a(n):
A. Acid only
B. Base only
C. Acid or base
D. None of the above

Answer 3

C. Acid or base

Question 4

4. Salts of weak acids or weak bases are:
   A. Completely ionized in solution
   B. Partially ionized in solution
   C. There is no rule of thumb regarding their ionization

Answer 4

A. Completely ionized in solution

Question 5

5. Strong electrolytes include:
A. Strong acids
B. Strong bases
C. All salts
D. A and B
E. A,B and C

Answer 5

E. A,B and C

Question 6

6. Which statement is true?
   A. There are no drugs that are more active when in the ionic state
   B. Some drugs are more active when in the ionic state
   C. All drugs are more active when in the ionic state

Answer 6

B. Some drugs are more active when in the ionic state

Question 7

7. In general, the ionized forms are:
   A. More water-soluble but much less soluble in lipid
   B. More lipid-soluble but much less soluble in water (un-ionized form)
   C. There is no rule of thumb that connects ionization to solubility in water or lipids.

Answer 7

A. More water-soluble but much less soluble in lipid

Question 8

8. If an acid or base is added to water, the pH of the latter is changed:
   A. Slightly
   B. Markedly

Answer 8

B. Markedly

Question 9

9. “In a general way, the concentration of acid in a weak-acid/conjugate-base buffer determines the capacity to neutralize added base”. This statement is:
   A. True
   B. False

Answer 9

A. True

Question 10

10. A characteristic of buffered solutions is that they undergo ______ of the pH upon addition of acid or base:
    A. No changes
    B. Small Changes
    C. Substantial changes

Answer 10

B. Small Changes

Question 11

11. For both weak acids and bases, the amount of drug that is ionized if the pH of the solution is equal to the drug’s pKa is:
A. 0%
B. 25% 
C. 50% 
D. 75% 
E. 100%

Answer 11

C. 50%

Question 12

12. Henderson-Hasselbach equation may be used to calculate:
    A. The approximate values of pH of buffer solutions
    B. The ratios of molar concentrations of a buffer system required to produce a
    solution of specific pH
    C. The pka of an acid or base
    D. A and C are correct
    E. A, B, and C are correct

Answer 12

E. A, B, and C are correct

Question 13

13. Buffered solution A consists of 0.01 M acetic acid and 0.01 M sodium acetate. Buffered solution B consists of 0.05 M acetic acid and 0.05 M sodium acetate. Will the 2 solutions have the same pH?
    A. Yes
    B. No

Answer 13

A. Yes

Question 14

14. When the buffer is equimolar in the concentrations of weak acid and conjugate base, or of weak base and conjugate acid, it has equal buffer capacity toward added strong acid or strong base. This statement is:
    A. True
    B. False

Answer 14

A. True

Question 15

15. “In relative terms, diffusion is a slow process”. This statement is:
    A. True
    B. False

Answer 15

A. True

Question 16

16. “The diffusion of a drug through a polymeric membrane involves dissolution of the drug in the matrix of the membrane”. This statement is:
    A. True
    B. False

Answer 16

A. True

Question 17

17. Diffusion is mostly influenced by the:
    A. Relative size of the penetrating molecules
    B. Diameter and shape of the pores
    C. A and B
    D. None of the above

Answer 17

C. A and B

Question 18

18. The diffusing molecules (diffusants)
    A. Pass through the tortuous pores formed by the overlapping strands of
    polymer
    B. Dissolve in the polymer matric and pass through the film by simple diffusion.
    C. Both A and/or B may be correct

Answer 18

C. Both A and/or B may be correct

Question 19

19. The tension between which phases is interfacial?
A. Gas phase and gas phase
B. Gas phase and liquid phase
C. Gas phase and solid phase
D. Liquid phase and solid phase
E. None of the above

Answer 19

D. Liquid phase and solid phase

Question 20

20. Main classes of surfactants include:

Answer 20

A. Amphoteric
B. Anionic
C. Cationic
D. Non-ionic

Question 21

21. Which non-ionic surfactants are more hydrophilic, tweens or spans?
    A. Tweens
    B. Spans
    C. Tweens and spans are equally hydrophilic

Answer 21

A. Tweens

Question 22

22. An increase in polyoxyethylene chains length would:
    A. Increase HLB
    B. Decrease HLB
    C. Not affect HLB

Answer 22

A. Increase HLB

Question 23

23. Adsorption from solution on to solid surfaces may occur if:
    A. Dissolved molecules and the solid surface have chemical groups capable of
    interacting
    B. Solute is surface active
    C. Surface area of the solid is high
    D. A and B only
    E. A, B, and C are correct

Answer 23

E. A, B, and C are correct

Question 24

24. The greater the affinity of the solute for the liquid, the ____ the tendency to adsorb to a solid.
    A. Higher
    B. Lower

Answer 24

B. Lower

Question 25

25. The more polar the solute, the adsorption that occurs from water will be:
    A. Increased
    B. Decreased
    C. Unaffected

Answer 25

B. Decreased

Question 26

26. Adsorption will tend to be greatest when the solute is in its:
    A. Ionized form
    B. Unionized form
    C. Ionization does not affect adsorption

Answer 26

B. Unionized form

Question 27

27. Adsorption will tend to be greatest at:
    A. High pH for weak acids; low pH for weak bases
    B. Low pH for weak acids; high pH for weak bases

Answer 27

B. Low pH for weak acids; high pH for weak bases