Burning a hydrocarbon fuel in a limited supply of air can produce carbon monoxide. Which statement correctly explains why carbon monoxide is harmful to humans?

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Question

Burning a hydrocarbon fuel in a limited supply of air can produce carbon monoxide. Which statement correctly explains why carbon monoxide is harmful to humans?

Accepted Answer

It reacts with haemoglobin, reducing oxygen transport in the blood — Carbon monoxide binds irreversibly to haemoglobin in red blood cells, forming carboxyhaemoglobin, which prevents oxygen from being transported and can be fatal. Dissolving in rainwater to form acid is the mechanism for sulfur dioxide producing acid rain. Carbon dioxide, not carbon monoxide, is the main greenhouse gas from combustion. Photochemical smog involves nitrogen oxides and unburned hydrocarbons, not carbon monoxide directly.

Answer

It dissolves in rainwater to form an acidic solution

Answer

It reacts with nitrogen oxides to form photochemical smog

Answer

It reacts with haemoglobin, reducing oxygen transport in the blood

Answer

It causes the greenhouse effect by absorbing infrared radiation

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