Question

If you wanted to go into the lab and emulate the buffer solution that exists in your blood which combination of compounds would you mix together to create your buffer? Explain your choice.
a) H2CO3 and KHCO3
b) KHCO3 and K2CO3
c) H2CO3 and K2CO3

Answer 1

Answer:

(a) $H_{2} CO_{3}$ and$KHCO_{3}$

Explanation:

Human blood contains a buffer of carbonic acid ($H_{2}CO_{3}$) and bicarbonate anion ($HCO_{3} ^{-}$) in order to maintain blood pH between 7.35 and 7.45, as a value higher than 7.8 or lower than 6.8 can lead to death. In this buffer, hydronium and bicarbonate anion are in equilibrium with carbonic acid. Furthermore, the carbonic acid in the first equilibrium can decompose into $CO_{2}$ gas and water, resulting in a second equilibrium system between carbonic acid and water. Because $CO_{2}$  is an important component of the blood buffer, its regulation in the body, as well as that of $O_{2}$ , is extremely important. The effect of this can be important when the human body is subjected to strenuous conditions.

In the body, there exists another equilibrium between hydronium and oxygen which involves the binding ability of hemoglobin. An increase in hydronium causes this equilibrium to shift towards the oxygen side, thus releasing oxygen from hemoglobin molecules into the surrounding tissues/cells. This system continues during exercise, providing continuous oxygen to working tissues.