Acid/Bases

Question 1

chemical equilibrium is

Answer 1

dynamic

Question 2

Law of mass action

Answer 2

A +B –> C + D

Question 3

Vf=

Answer 3

vf = kf[A][B]

Question 4

V r=

Answer 4

vr = kr[C][D]

Question 5

equilibrium constant Keq =

Answer 5

Keq = kf / kr = [C][D] / [A][B]

Question 6

Water is in equilibrium with its

Answer 6

component ions H+ and OH-

Question 7

pH Cytosol

Answer 7

6.9

Question 8

pH Gastric juice

Answer 8

1.4 -3.0

Question 9

pH of urine

Answer 9

5-8

Question 10

An acid is a compound or chemical group that acts as a

Answer 10

proton donor

Question 11

An base is a

Answer 11

compound or chemical group that acts as a proton acceptor

Question 12

The equilibrium between and acid and its conjugate base in aqueous solution,

Answer 12

HA +H2O –> H3O+ + A- ,

is usually abbreviated to HA –>H+ + A-

Question 13

Strong acids like HCl and bases like NaOH are

Answer 13

completely dissociated in water whereas weak acids and bases are reversibly protonated and deprotonated.

Question 14

Many drugs, amino acids, peptides, proteins and nucleic acids are

Answer 14

weak acids or bases.

Question 15

The strength of an acid or base is a measure of

Answer 15

its propensity to either donate or accept protons measured as its pKa

Question 16

the _____ the pKa, the stronger the acid

Answer 16

lower

Question 17

the _____ the pKa, the strong the base

Answer 17

higher

Question 18

pKa =

Answer 18

-log Ka = - log ([H+] [A-]/[HA])

Question 19

Ka =

Answer 19

[H+] [A-]/[HA]

Question 20

examples of medically important weak bases

Answer 20

purine: amphentamines
procainamide

pyrimides: nortiptylene
local anesthetics

Question 21

pH strongly affects

Answer 21

enzymatic activity

Question 22

pH also affects

Answer 22

drug availability

Question 23

For drugs with ionizable groups, a critical factor governing uptake and excretion will be the

Answer 23

pH of the local environment.

Question 24

When an acid or base is 50% deprotonated and 50 % protonated then

Answer 24

pH=pKa

Question 25

A buffer is a mixture of

Answer 25

a weak acid HA

and its conjugate base A-

Question 26

The____marks a “speedbump” in the titration curve

of a weak acid or base

Answer 26

pKa

Question 27

The _____ buffer system is the most important regulator of extracellular pH.

Answer 27

bicarbonate

Question 28

H-H equation for bicarbonate

Answer 28

pH = 6.1 + log [HCO3-]mM/ .03Pco2mmHg

Question 29

normal Pco2=

Answer 29

40mmHg,

Question 30

normal [CO2]d =

Answer 30

1.2 mM.

Question 31

Normal [HCO3-] =

Answer 31

24 mM

Question 32

Bicarbonate buffer rxn 2 is catalyzed by

Answer 32

carbonic anhydrase

Question 33

The bicarbonate buffer system is OPEN modulated by regulation of

Answer 33

CO2 loss in the lung and H+ /HCO3- excretion in the kidney allowing the system to be an effective buffer 1.3 units above its pKa

Question 34

[A-] is the

Answer 34

concentration of the proton acceptor (base)

Question 35

[HA] is the

Answer 35

concentration of the proton donor (acid).

Question 36

pH of arterial blood: =

Answer 36

7.4

Question 37

pH of venus blood: =

Answer 37

7.3

Question 38

[HCO3-] is ____

Answer 38

24mM

Question 39

pCO2 =

Answer 39

40mmHg

Question 40

Weak acids and their conjugate base exist as

Answer 40

2 equilibrium reactions that oppose and thereby stabilize each other.

Question 41

As base is added, it can be

Answer 41

protonated by the acid and turned into water.

Question 42

As acid is added, it can be

Answer 42

deprotonated by the base or taken up by the base to form a neutral product.

Question 43

In the buffering range, the addition of acid or base has

Answer 43

little impact on the pH of the solution, as seen on a titration curve.