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Unformatted text preview: is a significant change in pH.
• Buffer capacity depends on the concentration of the
buffering reagents. Buffer system : HA / A − [ H A]
[H ] = Ka
[ A− ]
+ [A - ]
pH = pK a + log
[HA] The greater the amounts of conjugate acid-base pair,
the greater the buffer capacity.
pH = pK a ± 1 A buffer is most effective when the buffering pair has
equal capacity to counteract additional H+ or OH- Predict
Predict the most effective pH range for each pair
of buffer agents.
pH = pK ± 1
a Effective pH? pK a ±1 3.17
5.74 (a) Find the pH of a buffer that is 0.350 M in formic acid
and 0.400 M in sodium formate? Ka= 1.8 × 10-4.
pH = pKa + log ([A-1]/...
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This document was uploaded on 02/26/2014.
- Fall '14