State true or false :
Carbon monoxide is a poisonous gas.

Explanation

**Step-by-Step Solution:**

1. **Identify the Substance**: The question asks about carbon monoxide (CO).

2. **Understand the Properties of Carbon Monoxide**: Carbon monoxide is a colorless, odorless, and tasteless gas.

3. **Determine Toxicity**: Carbon monoxide is known to be poisonous. It can bind with hemoglobin in the blood more effectively than oxygen, which prevents oxygen from being transported throughout the body.

4. **Explain the Mechanism of Poisoning**: When carbon monoxide binds to hemoglobin, it forms carboxyhemoglobin. This compound is much more stable than the oxygen-hemoglobin complex, leading to reduced oxygen delivery to tissues.

5. **Conclude the Statement**: Given the properties and effects of carbon monoxide, we can conclude that the statement "Carbon monoxide is a poisonous gas" is true.

**Final Answer**: True.

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