Chapter 15, Problem 73E

Carbon monoxide replaces oxygen in oxygenated hemoglobin according to the reaction:

   ${\text{HbO}}_{\text{2}}\left(\text{aq}\right)+\text{CO}\left(\text{aq}\right)\rightleftharpoons \text{HbCO}\left(\text{aq}\right)+{\text{O}}_{\text{2}}\left(\text{aq}\right)$

a. Use the reactions and associated equilibrium constants at body temperature to find the equilibrium constant for the reaction just shown.
   $\text{Hb}\left(\text{aq}\right)+{\text{O}}_{\text{2}}\left(\text{aq}\right)\rightleftharpoons {\text{HbO}}_{\text{2}}\left(\text{aq}\right)$K_c= 1.8
   $\text{Hb}\left(\text{aq}\right)+\text{CO}\left(\text{aq}\right)\rightleftharpoons \text{HbCO}\left(\text{aq}\right)$K_c= 306
b. Suppose that an air mixture becomes polluted with carbon monoxide at a level of 0.10%. Assuming the air contains 20.0% oxygen and that the oxygen and carbon monoxide ratios that dissolve in the blood are identical to the ratios in the air, what is the ratio of HbCO to HbO₂ in the bloodstream? Comment on the toxicity of carbon monoxide.