`XeF_(6)` is not stored in glass or quartz vessels. Why ?

Answer

### Step-by-Step Solution:

1. **Understanding the Chemical Nature of XeF6**:
- Xenon hexafluoride (XeF6) is a highly reactive compound. It can react with various materials, including glass and quartz.

2. **Reactivity with Glass and Quartz**:
- Glass and quartz are primarily composed of silicon dioxide (SiO2). When XeF6 comes into contact with SiO2, a chemical reaction occurs.

3. **Formation of Xenon Trioxide (XeO3)**:
- The reaction between XeF6 and SiO2 can be represented as:
\[ 2 \, \text{XeF}_6 + 3 \, \text{SiO}_2 \rightarrow 2 \, \text{XeO}_3 + 6 \, \text{SiF}_4 \]
- This reaction produces xenon trioxide (XeO3) and silicon tetrafluoride (SiF4).

4. **Explosive Nature of XeO3**:
- Xenon trioxide (XeO3) is known to be explosive. Therefore, storing XeF6 in glass or quartz vessels would lead to the formation of this dangerous compound.

5. **Safe Storage Conditions**:
- Due to the risk of forming an explosive compound, XeF6 is stored in nickel containers, which do not react with it, ensuring safe storage.

### Final Answer:
XeF6 is not stored in glass or quartz vessels because it reacts with silicon dioxide (SiO2) to form xenon trioxide (XeO3), which is explosive in nature. Instead, it is stored in nickel containers to avoid this reaction.

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