The pH of human blood is 6.8~7.8, the pKa of (4)deoxyhomoglobinA is 8.2, the pKa of (2)oxyhomoglobinA is 6.96, it assumed that(1)logP₀ and (2)logP₀ or (3)logP₀ and (4)logP₀ are approximately the same value. The yellow region in fig-5 The yellow region in fig-5 is the region of 6.8≦pH≦7.8. and the region of ΔrG₀total = ー2.3RT[{(3) logPー(1)logP }+{(2) logPー(4)logP }] = 2.3RT[{(1) logPー(3)logP }+{(4)