Re: Stuck on a Biochemistry question

Ash wrote:
"Jimchip" <jimchip@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in
message news:1256hendogsal09@xxxxxxxxxxxxxxxxxxxxx
On 2006-04-29, Ash <mail@xxxxxxxx> wrote:
If anyone out there has done this before, and is bored enough to
have a look
at it again, any help would be greatly appreciated (its the last
question and i cant do it :P):

"A newly discovered insect squirts out formic acid (Ka = 1.8 x
10-4) as a defensive mechanism. An analysis of this liquid shows
the concentration of
formate ion to be 0.015M and the total concentration of formate plus
formic
acid to be 1.45M. What is the pH of this liquid? Hint: pH = pKa +
log([A]/[HA])"

Formic acid= HA
Formate = A-

pH = pKa + log([formate])/[formic acid])

--
Henderson-Hasselbach equation


How come such a simple equation (it's only a rearrangemt of HA === H+ + A-
and logged) earned two people immortality?


.

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