Which of the following gas mixture is used by the divers inside the sea ?

Options

A. `O_(2)+He`
B. `O_(2)+Xe`
C. `O_(2)+Ar`
D. `O_(2)+N_(2)`

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks about the gas mixture used by divers when they go underwater.

2. **Identifying the Risks of Diving:**
As divers descend into the sea, they face various risks, including changes in pressure and the need for adequate breathing gas.

3. **Recognizing the Importance of Gas Mixtures:**
The composition of the gas mixture is crucial for safe diving. Traditional air (which is about 78% nitrogen and 21% oxygen) can lead to nitrogen narcosis and oxygen toxicity at greater depths.

4. **Introduction to Heliox:**
One of the gas mixtures used by divers is called "heliox," which consists of helium and oxygen.

5. **Composition of Heliox:**
Heliox typically contains about 80% helium and 20% oxygen. This mixture helps to reduce the risks associated with high pressure and nitrogen narcosis.

6. **Advantages of Helium:**
Helium is chosen because it is less soluble in blood compared to nitrogen, which minimizes the risk of decompression sickness and allows for safer breathing at depth.

7. **Conclusion:**
Therefore, the correct answer to the question is that divers use heliox (a mixture of helium and oxygen) when diving underwater.

**Final Answer:**
The gas mixture used by divers inside the sea is heliox (80% helium and 20% oxygen).

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