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Q.
Carbon monoxide is a poisonous .gas, the antidote used for this poisoning is :
AFMCAFMC 2001
Solution:
$CO$ is quite poisonous because it combines with the haemoglobin of red blood cells to form carboxy-haemoglobin and thus it does not allow blood to carry oxygen. Carbogen is used as an antidote for $CO$ poisoning and contain $90\% O_{2} $ .