Buffer System

Question 1

Water molecules forms dipole.

T/F

Answer 1

T

Question 2

Water molecules forms hydrogen bonds.

T/F

Answer 2

T

Question 3

the molar concentration of H+ ions (or of OH− ions) in pure water is the product of the probability, ______ , times the _________

The result is ________ mol/L.

Answer 3

1.8 ×10−9

molar concentration of water, 55.56 mol/L.

1.0×10−7

Question 4

pH IS THE ________ OF THE ______

Answer 4

NEGATIVE LOG

HYDROGEN ION CONCENTRATION

Question 5

The term pH was introduced in ____ by _______ , who defined pH as the negative log of the hydrogen ion concentration:

Mathematically,
pH = __________

Answer 5

1909

Sörensen

˗ log [H+]

Question 6

For example, for pure water at 250C,

 ˗ log [H+] =  ˗ log [\_\_\_] = - [\_\_\_] =\_\_\_

Answer 6

10-7

-7

7

Question 7

Acids are proton _____ and bases are proton ____.

Answer 7

donors

acceptors

Question 8

Strong acids (eg, HCl or H2SO4) (completely or partially?) dissociate into ____ and ____ even in strongly acidic solutions (low pH).

Weak acids dissociate (completely or partially?) in acidic solutions.

strong bases (eg, KOH or NaOH) are (completely or partially?) dissociated at high pH.

Answer 8

Completely

anions and cations

Partially

Completely

Question 9

Milk is acidic

T/F

Answer 9

F

Slightly acidic

Question 10

Henderson-Hasselbalch equation,

???

Answer 10

Ph = pka + log(salt / acid)

Question 11

Hasselbach equation

when the concentrations of base and acid are the same, then pH is ______.

Thus, when the acid is _______, pH and pKa have the same values.

Answer 11

equal to pKa

half ionized

Question 12

Buffers are solutions which can _______ in pH when ______ is added.

Answer 12

resist changes

acid or alkali

Question 13

Factors Affecting pH of a Buffer

The pH of a buffer solution is determined by two factors:

The value of pK: The lower the value of pK, the (lower or higher?) is the pH of the solution.

Answer 13

Lower

Question 14

the buffer capacity is determined by the _________ of ______ present, as well as by their __

Answer 14

actual concentrations

salt and acid

ratio

Question 15

Buffering capacity is the ____________ which is necessary for a change in pH of ____________ of buffer solution.

Answer 15

number of grams of strong acid or alkali

one unit of one liter

Question 16

The buffering capacity of a buffer is defined as the ability of the buffer to resist changes in pH when an acid or base is added.

T/F

Answer 16

T

Question 17

Three major buffering systems

Answer 17

Protein buffering system

Hemoglobin buffer system

Carbonate acid- Bicarbonate

Question 18

Major buffers in the ICF

major buffers in the ECF

Answer 18

Phosphate buffer and protein buffer system

Carbonic acid bicarbonate and protein buffer system

Question 19

Protein buffering system

If pH climbs, the ____ group of amino acid acts as a _____

If the pH drops, the ____ group acts as a ____

Answer 19

carboxyl; weak acid

amino; weak base

Question 20

Hemoglobin buffer system

Prevents pH changes when PCO2 is rising or falling

T/F

Answer 20

T

Question 21

Carbonic acid-bicarbonate buffer system

Has the following limitations:

(Can or Cannot?) protect the ___ from ___ changes due to increased or depressed ___

Only functions when _______ and _______ are working normally

It is limited by availability of _____________

Answer 21

Cannot ; ECF; ph ; CO2 levels

respiratory system and control centers

bicarbonate ions (bicarbonate reserve)

Question 22

Maintenance of acid-base balance

Lungs help regulate pH through _________________ buffer system

Kidneys help regulate pH through _____

Answer 22

carbonic acid - bicarbonate

renal compensation