A) Consider how best to prepare one liter of a buffer solutionwith pH = 4.94 using one of the weakacid/conjugate base systems shown here.

Weak Acid	Conjugate Base	Ka	pKa
HC2O4-	C2O42-	6.4 x 10-5	4.19
H2PO4-	HPO42-	6.2 x 10-8	7.21
HCO3-	CO32-	4.8 x 10-11	10.32

How many grams of the potassium salt of the weakacid must be combined with how many grams of thepotassium salt of its conjugate base, to produce1.00 L of a buffer that is 1.00 Min the weak base?

grams potassium salt of weak acid =

grams potassium salt of conjugate base =

B) Design a buffer that has a pH of 3.75 usingone of the weak acid/conjugate base systems shown below.

Weak Acid	Conjugate Base	Ka	pKa
HC2O4-	C2O42-	6.4×10-5	4.19
H2PO4-	HPO42-	6.2×10-8	7.21
HCO3-	CO32-	4.8×10-11	10.32

How many grams of the sodium salt of the weak acidmust be combined with how many grams of the sodiumsalt of its conjugate base, to produce 1.00 L of abuffer that is 1.00 M in the weak base?

grams sodium salt of weak acid=  g

grams sodium salt of conjugate base=  g

C) Consider how to prepare a buffer solution with pH =9.52 (using one of the weak acid/conjugate basesystems shown here) by combining 1.00 L of a0.301-M solution of weak acid with0.365 M potassium hydroxide.

Weak Acid	Conjugate Base	Ka	pKa
HNO2	NO2-	4.5 x 10-4	3.35
HClO	ClO-	3.5 x 10-8	7.46
HCN	CN-	4.0 x 10-10	9.40

How many L of the potassium hydroxide solutionwould have to be added to the acid solution of yourchoice?

Design a buffer that has a pH of 7.29 using oneof the weak base/conjugate acid systems shown below.

Weak Base	Kb	Conjugate Acid	Ka	pKa
CH3NH2	4.2×10-4	CH3NH3+	2.4×10-11	10.62
C6H15O3N	5.9×10-7	C6H15O3NH+	1.7×10-8	7.77
C5H5N	1.5×10-9	C5H5NH+	6.7×10-6	5.17

D) How many grams of the chloride salt of theconjugate acid must be combined with how many grams of the weakbase, to produce 1.00 L of a buffer that is1.00 M in the weak base?

grams chloride salt of conjugate acid =

grams weak base =