[okasa]

Hi, can anyone help me to solve this problem:

Gas-solution equilibrium: Hemoglobin can form a complex with either O2 or CO. For the reaction:
         O2Hb(aq) + CO (g) = COHb (aq)  + O2(g)
at body temperature, K=200. If the ratio [COHb]/[O2Hb] comes close to 1, death is probable. What concentration of CO in the air is likely to be fatal? (Assume that the partial pressure of O2 is 0.2 atm and the air temperature is 25oC)
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What should I start to solve this problem. I always confuse with heterogeneous equilibrium's problem.

Please help me.

Thanks.

[okasa]

Is it true if:
K=Kc.Kp = [COHb].pO2/[O2Hb].pCO
then K= pO2/pCO => pCO => [CO]=pCO/RT ?