Suggest a reason as to why CO is poisonous.
CO is poisonously coming from the fact that it binds itself readily with an iron atom of the haemoglobin (Hb) present in the red blood cell to form carboxyhaemoglobin.
Consequently, when inhaled along with air, it combines with haemoglobin (Hb) readily than oxygen to form a stable carboxyhaemoglobin complex as compared to oxyhaemoglobin complex. As a result, the amount of haemoglobin available for oxygen transport decreases. In other words, this results in a lack of O2 supply for metabolic action. Higher concentration of CO causes dizziness and if exposure to CO continues, it leads to death. Thus the highly poisonous nature of CO arises due to its ability to form a stable complex with haemoglobin which is about 300 times more stable than the oxygen haemoglobin complex.
