chemistry

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I asked this question earlier that drbob explained but i still do not really understand what to do. can you please make it clearer?

the average pH of healthy human blood is 7.4. how many moles of H+ ions are free in your blood. The average person has approx. 5 L of blood.

Responses

chemistry - DrBob222, Monday, May 25, 2009 at 12:45pm
I assume the question is asking simply to count the H^+ free (from the pH calculation) and NOT go through the bicarbonate equilibrium.
pH = -log(H^+).
Solve this for (H^+) which gives the hydrogen ion in moles/L, then multiply by 5 to obtain the moles in 5 L.

would the equation be 7.4= -log of what?

• chemistry - ,

Sure.
pH = -log(H^+).
7.4 = -log(H^+)
-7.4 = log(H^+)
(H^+) = 3.98 x 10^-8 moles/Liter.
3.98 x 10^-8 moles/L x 5 L = ?? moles (H^+).
Again, I have assumed that the problem is concerned only with the free hydrogen ions and not the small amount of H^+ that may come from the bicarbonate/CO2 system that acts as a buffer for the blood system.

• chemistry - ,

oh ok...thankyou