Question

Design a buffer that has a pH of 4.45 using one of 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

How many grams of the chloride salt of the conjugate acid must be combined with how many grams of the weak base, to produce 1.00 L of a buffer that is 1.00 M in the weak base?

grams chloride salt of conjugate acid =

grams weak base =

Design a buffer that has a pH of 6.65 using one 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 acid must be combined with how many grams of the sodium salt of its conjugate base, to produce 1.00 L of a buffer that is 1.00 M in the weak base?

grams sodium salt of weak acid =

grams sodium salt of conjugate base =

Answer 1