Module 12: Buffers

Question 1

What are buffers?

Answer 1

Solutions that have a weak acid & its conjugate base
- or a weak base & its conjugate acid

Question 2

What do buffers do?

Answer 2

They help resist change in pH when a strong acid/base is added to the solution

Question 3

What is a buffer capacity?

Answer 3

(+/-)1 of buffer pH

limit before the buffer is destroyed

(limit to the amount of acid/base that can be added before buffer loses its ability to resist change)

Question 4

Buffer capacity is _____ above or below buffer pH

Answer 4

1

Question 5

What is the main buffering system?

Answer 5

Blood buffering system

Question 6

What are the 3 buffering systems in the body?

Answer 6

1. Blood
2. Respiratory
3. Renal

• Bicarbonate
• Phosphate
• Protein

Question 7

The ______ & _______ systems helps control the blood pH buffering system

Answer 7

repiratory
renal

Question 8

How does the respiratory buffering system work?

Answer 8

Carbonic acid buffer system

effects CO2 blood levels

When CO2 is dissolved in blood it produces carbonic acid –> if we are having issues with breathing out or respiratory depression (holding on to too much CO2) –> buildup of CO2 –> more carbonic acid in blood –> decreased pH

Question 9

Increasing CO2 in the blood =

Answer 9

Decreases pH

Question 10

How does the renal buffering system work?

Answer 10

Various buffer systems to remove hydrogen ions through the kidneys

Question 11

What is another name for the blood buffering system?

Answer 11

Bicarbonic buffering system

Question 12

What is the blood buffering system equilibrium equation?

Answer 12

2H₂O + CO₂ <==> H₂CO₃ + H₂O <==> H₃O+ + HCO₃-

Question 13

What is happening during the blood buffering system?

Answer 13

Water & CO2 are producing Carbonic acid (H₂CO₃) & interacting w/ more water to produce H₃O & bicarbonic

2H₂O + CO₂ <==> H₂CO₃ + H₂O <==> H₃O+ + HCO₃-

Question 14

What does Le Chatelier’s principle state?

Answer 14

When a system at equilibrium is disturbed, the system will adjust to re-establish equilibrium

Question 15

What is Carbonic acid?

Answer 15

H₂CO₃

Question 16

What is bicarb?

Answer 16

HCO₃-

Question 17

If we increases CO2 in the blood buffering system, what would happen?

Answer 17

Equilibrium which shift to the right

Increase in carbonic acid = decrease in pH

Question 18

If you are adding a solute to an equilibrium equation, equilibrium shift to the ________ side.

Answer 18

opposite

Question 19

What are the 3 main components of the blood buffering system?

Answer 19

1. CO2
2. Carbonic acid
3. Bicarbonic

Question 20

In a buffer, what happens if your conjugate pair goes away?

Answer 20

Buffer is destroyed

Question 21

In a buffer math problem, how do you identify the acid?

Answer 21

(+)

Question 22

What is charge controlled by?

Answer 22

pH of the solution
pKa of the drug

Question 23

T/F: ionized drugs can cross barriers

Answer 23

F

Only unionized