Question

carbon _________ is a colorless, odorless, and poisonous gas.

a monoxide
b dioxide
c trioxide

Explanation:

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<reasoning>

Analyze the question stem

The question asks to identify a specific compound of carbon that is a colorless, odorless, and poisonous gas.

Evaluate the options

• Carbon monoxide (\(\text{CO}\)) is a highly toxic, colorless, and odorless gas. It binds strongly to hemoglobin in red blood cells, preventing oxygen transport.
• Carbon dioxide (\(\text{CO}_2\)) is colorless and odorless, but it is not classified as a poisonous gas under normal conditions (though it is an asphyxiant at very high concentrations).
• Carbon trioxide (\(\text{CO}_3\)) is an unstable oxide of carbon that does not exist as a stable gas under standard conditions.

Determine the correct answer

Based on the chemical properties, carbon monoxide perfectly matches the description of being a colorless, odorless, and poisonous gas.
</reasoning>

<answer>
<mcq-correct>a monoxide</mcq-correct>
<mcq-option>b dioxide</mcq-option>
<mcq-option>c trioxide</mcq-option>
</answer>

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Answer:

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<reasoning>

Analyze the question stem

The question asks to identify a specific compound of carbon that is a colorless, odorless, and poisonous gas.

Evaluate the options

• Carbon monoxide (\(\text{CO}\)) is a highly toxic, colorless, and odorless gas. It binds strongly to hemoglobin in red blood cells, preventing oxygen transport.
• Carbon dioxide (\(\text{CO}_2\)) is colorless and odorless, but it is not classified as a poisonous gas under normal conditions (though it is an asphyxiant at very high concentrations).
• Carbon trioxide (\(\text{CO}_3\)) is an unstable oxide of carbon that does not exist as a stable gas under standard conditions.

Determine the correct answer

Based on the chemical properties, carbon monoxide perfectly matches the description of being a colorless, odorless, and poisonous gas.
</reasoning>

<answer>
<mcq-correct>a monoxide</mcq-correct>
<mcq-option>b dioxide</mcq-option>
<mcq-option>c trioxide</mcq-option>
</answer>

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