M3 DRILLS

Question 1

How many liters of a mouthwash can be prepared from 100 mL of cinnamon flavor if its concentration is to be 0.5% (v/v)?

A.
10 L

B.
15 L

C.
20 L

D.
18 L

Answer 1

C1V1=C2V2

(100mL) (100%) = (xmL) (0.5%) x= 20,000mL = 20L

The correct answer is:
20 L

Question 2

At what number is degrees Fahrenheit and degrees Celsius the same?

A.
-24

B.
-40

C.
0

D.
7

Answer 2

B

Question 3

Van’t-Hoff equation

A.
P=nRT

B.
P= VRT

C.
P= MRT

D.
P=CVRT

Answer 3

Derived from PV=nRT P=n/V RT

n/V= Molarity

The correct answer is:
P= MRT

Question 4

What is the final concentration of ethanol in a solution prepared by mixing 600 mL of 70% ethanol, 150 mL of 85% ethanol, and 250 mL of 95% ethanol?

A.
67.8%

B.
77.3%

C.
78.5%

D.
87.6%

Answer 4

[(600 x 0.7) + (150 x 0.85) + (250 x 0.95)] / 1000 x 100%

The correct answer is:
78.5%

Question 5

Prescriber’s order: Tobramycin 1% ophth sol,10mL Available tobramycin solution: 40mg/mL (E=0.07) Determine the amount of NaCl that needs to be added to the product isotonic.

A.
90 mg

B.
7 mg

C.
82 mg

D.
1 g

Answer 5

0.9g/100mL × 1000mg/g × 10mL = 90mg NaCl

1g/100mL × 1000mg/g × 10mL × 0.07 = 7mg NaCl equivalent 90mg – 7mg = 82mg NaCl needed

The correct answer is:
82 mg

Question 6

100 mLFor the above problem, determine amount of tobramycin stock solution to be added to the solution.

A.
100 mL

B.
1 mL

C.
4 mL

D.
2.5 mL

Answer 6

1000mg/100mL × 10mL × 1mL/40mg = 2.5mL

The correct answer is:
2.5 mL