Buffer Prep (LAB) Flashcards
Acids taste ____
SOUR
states that acid donates a proton while bases accepts a proton
Brownsted-Lowry
for both Arrhenius and Bronsted Lowry concepts an acid or base disassociates or ionizes in water
Water
mixture of a weak acid/base and its conjugate base/acid
buffers
typically pH sensitive, thus an appropriate buffer is needed to preserve their native confirmation or shape
biomolecules
mixture of a weak acid and its conjugate base
buffer
Can resist drastic changes in pH
buffer
used in calculating the pH of buffers
Henderson-Hasselbach equation
proton (H+) donor
weak acid
partially dissociates and donates its hydrogen atom to another substance typically water
weak acid
loses its H+ and forms a conjugate base (A-)
weak acid
what forms after the water molecule accepts a proton
hydronium cation
has a constant value at a particular temperature
acid dissociation constant
dissociates partially by
donating its hydrogen atom to
form its conjugate base, acetate (CH3COO-) and a hydronium cation
acetic acid
identify the compounds
grade yourself accordingly
formula of henderson-hasselbalch
grade yourself accordingly
sample exercise, study on how they got the answer
grade yourself accordingly
molarity formula
moles/vol in L
recite formula of Molarity given mass, molar mass, and volume
check ppt for answer
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
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.
narrowly maintained around 7.40 (7.35-7.45) by biological buffer systems
physiologic pH
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
acid base disorderes
experiments in biochemistry require appropriate buffer system because these are highly pH sensitive
proteins, enzymes, nucleic acids
most common inorganic buffer system
phosphate buffer
weak triprotic acid that dissociates
phosphoric acid
an acid that has three dissociable protons that undergo stepwise ionization
triptoric acid
can be prepared using either H3PO4-H2PO4- or H2PO4-HPO4-2 system
phosphate buffer
recite preparation of phosphate buffers in 3 systems
grade yourself accordingly
if ___ pH is required, use H3PO4-H2PO4- buffer system
acidic
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
physiologic
aqueous solution that resist changes in pH upon the addition of a small amount of acid or base
buffer
Composed of weak acid and its conjugate base or weak base and its conjugate acid
buffer
Only ___ acid or __ base completely dissociates in water
strong
volume of liquid formula
check ppt for answer
