The main buffer in the blood consists primarily of hydrogen carbonate ions (HCO₃^–) and H₃O⁺ ions in equilibrium with water and CO₂:

This reaction assumes that all H₂CO₃ produced decomposes completely to CO₂ and H₂O. Suppose that 1.0 L of blood is removed from the body and brought to pH = 6.1.

(a) If the concentration of HCO₃ 2 is 5.5 μmol · L^–1, calculate the amount (in moles) of CO₂ present in the solution at this pH.

(b) Calculate the change in pH that occurs when 0.65 mmol H₃O⁺ is added to this sample of blood at this pH (that is, pH = 6.1). See Box 6G.1.

Transcribed Image Text:

H3O+ (aq) + HCO3(aq) = 2 H₂O(1) + CO,(aq) K 7.9 X 10-7