Buffer Prep (LAB)

Question 1

Acids taste ____

Answer 1

SOUR

Question 2

states that acid donates a proton while bases accepts a proton

Answer 2

Brownsted-Lowry

Question 3

for both Arrhenius and Bronsted Lowry concepts an acid or base disassociates or ionizes in water

Answer 3

Water

Question 4

mixture of a weak acid/base and its conjugate base/acid

Answer 4

buffers

Question 5

typically pH sensitive, thus an appropriate buffer is needed to preserve their native confirmation or shape

Answer 5

biomolecules

Question 6

mixture of a weak acid and its conjugate base

Answer 6

buffer

Question 7

Can resist drastic changes in pH

Answer 7

buffer

Question 8

used in calculating the pH of buffers

Answer 8

Henderson-Hasselbach equation

Question 9

proton (H+) donor

Answer 9

weak acid

Question 10

partially dissociates and donates its hydrogen atom to another substance typically water

Answer 10

weak acid

Question 11

loses its H+ and forms a conjugate base (A-)

Answer 11

weak acid

Question 12

what forms after the water molecule accepts a proton

Answer 12

hydronium cation

Question 13

has a constant value at a particular temperature

Answer 13

acid dissociation constant

Question 14

dissociates partially by
donating its hydrogen atom to
form its conjugate base, acetate (CH3COO-) and a hydronium cation

Answer 14

acetic acid

Question 15

identify the compounds

Answer 15

grade yourself accordingly

Question 16

formula of henderson-hasselbalch

Answer 16

grade yourself accordingly

Question 17

sample exercise, study on how they got the answer

Answer 17

grade yourself accordingly

Question 18

molarity formula

Answer 18

moles/vol in L

Question 19

recite formula of Molarity given mass, molar mass, and volume

Answer 19

check ppt for answer

Question 20

create a stepwise process for creation of buffer with the ff data

52.152g sodium acetate
2.00L volumetric flask
60.7 ml of acetic acid

Answer 20

Weigh 52.152g of sodium acetate using analytical balance then transfer it quantitively to a 2.00L volumetric flask.

Add 60.7 ml of acetic acid to the flask and then half-fill with distilled water and swirl to dissolve the solids

Fill to the 2.00 L mark, then shake thoroughly by inverting the flask several times.

Make sure that all the sodium acetate is dissolved completely. Check the pH using a pH meter and adjust the pH by adding HCl or NaOH if necessary.

Question 21

narrowly maintained around 7.40 (7.35-7.45) by biological buffer systems

Answer 21

physiologic pH

Question 22

deviation from the pH range of 7.35 to 7.45 may result to this, which consist of deleterious effects including possible death if left uncorrected

Answer 22

acid base disorderes

Question 23

experiments in biochemistry require appropriate buffer system because these are highly pH sensitive

Answer 23

proteins, enzymes, nucleic acids

Question 24

most common inorganic buffer system

Answer 24

phosphate buffer

Question 25

weak triprotic acid that dissociates

Answer 25

phosphoric acid

Question 26

an acid that has three dissociable protons that undergo stepwise ionization

Answer 26

triptoric acid

Question 27

can be prepared using either H3PO4-H2PO4- or H2PO4-HPO4-2 system

Answer 27

phosphate buffer

Question 28

recite preparation of phosphate buffers in 3 systems

Answer 28

grade yourself accordingly

Question 29

if ___ pH is required, use H3PO4-H2PO4- buffer system

Answer 29

acidic

Question 30

if _____ pH is needed, the H2PO4-HPO4-2 should be utilized because the equivalent pKa2 is already 7.21 which is very near the physiologic pH of 7.40

Answer 30

physiologic

Question 31

aqueous solution that resist changes in pH upon the addition of a small amount of acid or base

Answer 31

buffer

Question 32

Composed of weak acid and its conjugate base or weak base and its conjugate acid

Answer 32

buffer

Question 33

Only ___ acid or __ base completely dissociates in water

Answer 33

strong

Question 34

volume of liquid formula

Answer 34

check ppt for answer