In 1984, Bhopal gas tragedy was caused due to the leakage of

Options

A. potassium isocyanate
B. sodium monoxide
C. sodium thiocyanate
D. methyl isocyanate

Explanation

**Step-by-Step Solution:**

1. **Identify the Event**: The Bhopal gas tragedy occurred on December 3, 1984, in Bhopal, India. It is recognized as one of the worst industrial disasters in history.

2. **Understand the Cause**: The tragedy was caused by the leakage of a toxic gas from a pesticide plant operated by Union Carbide.

3. **Determine the Chemical Involved**: The primary chemical responsible for the gas leak was methyl isocyanate (MIC).

4. **Explain the Reaction**: When water came into contact with methyl isocyanate, it triggered an exothermic reaction. This reaction generated a significant amount of heat.

5. **Consequences of the Reaction**: The heat caused the safety valve of the storage tank to burst due to increased pressure. This violent rupture led to the release of a heavy gas that spread rapidly and affected the surrounding population.

6. **Health Impacts**: The gas leak resulted in severe health issues, including respiratory problems, partial or complete blindness, and gastrointestinal disorders among the local population.

7. **Conclusion**: Based on the options provided, the correct answer to the question is that the Bhopal gas tragedy was caused due to the leakage of methyl isocyanate.

**Final Answer**: Methyl isocyanate.

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