Dear student
Haemoglobin combines with oxygen to form oxyhaemoglobin.
One haemoglobin molecule can bind to 4 oxygen atoms.
Oxygenation of haemoglobin leads to the liberation of H+ ions in the medium. Therefore, oxy-Hb is the strongest acid.
Whereas carboxyhaemoglobin is formed by the combination of haemoglobin with carbon monoxide.
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