In 1984 the Bhopal gas tragedy took place because methyl isocyanate reacted with:

Options

A. DDT
B. Ammonia
C. `CO_(2)`
D. Water

Answer

**Step-by-Step Solution:**

1. **Understanding the Incident**: The Bhopal gas tragedy occurred in December 1984, specifically on the night of December 2nd and 3rd. It was a catastrophic gas leak incident that took place at the Union Carbide Pesticide Plant in Bhopal, India.

2. **Identifying the Gas Involved**: The gas that leaked during this tragedy was methyl isocyanate (MIC). This compound is known for its high toxicity and is used in the production of pesticides.

3. **Chemical Reaction**: Methyl isocyanate acts as an intermediate chemical in the synthesis of carbamate pesticides. When it comes into contact with water, it reacts to form carbamate compounds.

4. **Toxicity of the Reaction**: The carbamate pesticides produced from the reaction of methyl isocyanate with water are highly toxic. This toxicity is what led to the tragic loss of life during the incident.

5. **Conclusion**: Therefore, the answer to the question is that methyl isocyanate reacted with water, leading to the formation of highly toxic carbamate pesticides, which caused the Bhopal gas tragedy.

**Final Answer**: Methyl isocyanate reacted with water.

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