Why is dihydrogen not preferred in weather balloons these days?

Explanation

**Step-by-Step Solution:**

1. **Understanding Dihydrogen**: Dihydrogen (H₂) is a colorless, odorless gas that is highly flammable. Its properties make it a potential candidate for use in various applications, including weather balloons.

2. **Combustibility of Dihydrogen**: One of the main reasons dihydrogen is not preferred for weather balloons is its highly combustible nature. When dihydrogen comes into contact with oxygen in the presence of an ignition source, it can easily ignite and cause an explosion.

3. **Risk of Fire Accidents**: The risk of fire accidents is significantly increased when using dihydrogen in weather balloons. In the presence of air, dihydrogen can catch fire easily, which poses a serious safety hazard.

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