Tutorial 7 Flashcards
pH of blood plasma
7.4
pH of saliva
6.4-7.1
sweat
4.00-6.8
tears
7.2-7.4
urine
4.8-7.5
gastric juice
1.4-2
intestinal juice
6.3-8.0
pancreatic juice
7.5-8.8
interstitial fluid
6.3-8.0
intracellular fluid
6.0-7.2
cerebrospinal fluod
7.2-7.5
skin
6.2-7.5
The resistance to change in pH is known as ______ or ______
buffer action, buffer capacity
What is the pH of blood plasma?
• A) 7.4
• B) 6.8
• C) 4.0
• D) 7.2
A
Which of the following fluids has the lowest pH?
• A) Saliva
• B) Sweat
• C) Gastric juice
• D) Tears
C
What is the main role of buffers in pharmaceutical solutions?
• A) To change color
• B) To resist changes in pH
• C) To resist changes in taste
• D) To increase drug bioavailability
B
Which of the following buffers is made of citric acid and sodium citrate?
• A) Phosphate buffer
• B) Citrate buffer
• C) Acetate buffer
• D) Bicarbonate buffer
B
Which of the following is a weak acid/its salt buffer?
• A) Acetic acid and sodium acetate
• B) Sodium chloride and water
• C) Hydrochloric acid and sodium chloride
• D) Ammonia and ammonium chloride
A
What is the buffer capacity?
• A) The ability of a buffer to change pH
• B) The resistance to change in pH
• C) The ability to increase the solubility of a drug
• D) The resistance to oxidation
B
Which of the following pharmaceutical products need pH adjustment?
• A) Tablets
• B) Injections
• C) Eye drops
• D) Both B & C
D
What is the pH range of pancreatic juice?
• A) 6.3 - 7.5
• B) 1.4 - 2.0
• C) 7.5 - 8.8
• D) 6.0 - 7.2
7.5-8.8
What is the molar ratio of salt to acid required to prepare an acetate buffer solution of pH 5 if the pKa of acetic acid is 4.8?
• A) 7:1
• B) 1.58:1
• C) 5:1
• D) 0.2:1
B
True or False:
The pH of cerebrospinal fluid is always neutral (7.0).
Falsy – the pH of cerebrospinal fluid is between 7.2 and 7.5.
True or False:
Dilution of a buffer with water can change the pH of the solution.
Truey
True or False: Acetate buffers decrease in pH when temperature increases.
Falsy – the pH of acetate buffers increases with temperature.
The pH of urine ranges between ______ and ______.
4.8 and 7.5
When 1 mL of 0.1 M HCl is added to 100 mL of pure water, the pH drops from 7 to ______.
3
When a strong acid such as HCl is added to an acetate buffer, the ______ in the buffer ties up the H+ ions to minimize the pH change.
sodium acetate (salt)
The pH of sweat can range between ______ and ______.
4.0 and 6.8
Why don’t we usually use weak bases and their salts in buffers?
-Their volatility and instability
-their pH depends on pHw which is affected by temperature
_____ is the dissociation constant of the weak acid or the weak
base.
pKa
T or F:
The buffer system giving the best buffer capacity will be that containing an acid/base with a pKa closest to the desired pH of the solution
True
The buffer system giving the best buffer capacity will be that containing an _______ with a ____ closest to the desired ___of the solution
acid/base, pKa, pH
True or False:
The pH of saliva is typically more acidic than that of blood.
truey
Which fluid in the body is the most alkaline under normal conditions?
A) Gastric juice B) Urine C) Pancreatic fluid D) Blood
c
The pH of urine can vary widely, but it typically falls within which range?
A) 5.5 - 7.5 B) 3.0 - 4.0 C) 7.5 - 8.5 D) 4.8 - 7.5
d
Which body fluid is closest to neutral pH under normal conditions?
A) Cerebrospinal fluid B) Gastric juice C) Blood D) Pancreatic fluid
a
T or F;
The pH of blood is slightly alkaline.
Truey
Which buffer system primarily regulates the pH of the blood by balancing bicarbonate and carbonic acid?
A) Phosphate buffer system B) Protein buffer system C) Bicarbonate buffer system D) Ammonia buffer system
C
T or F:
The bicarbonate buffer system is the most important buffer system in extracellular fluids, including blood.
Truey
T or F:
he phosphate buffer system is the most important buffer system in extracellular fluids, including blood.
Falsy
it’s bicarbonate
In addition to the bicarbonate buffer system, which other buffer system plays a significant role in intracellular fluid?
A) Hemoglobin buffer system B) Protein buffer system C) Phosphate buffer system D) Ammonia buffer system
C
T or F:
Phosphate buffer system is the most important intracellular fluid buffer
Truey
