what is the chief constituent of pyrex glass ?

Options

A. `B_(2)O_(3)`
B. `SiO_(2)`
C. `Al_(2)O_(3)`
D. `Na_(2)O`

Answer

To determine the chief constituent of Pyrex glass, we can follow these steps:

### Step 1: Understand the Composition of Pyrex Glass
Pyrex glass is a type of borosilicate glass that is known for its high resistance to thermal shock. It is primarily made up of several components.

### Step 2: Identify the Main Components
The composition of Pyrex glass typically includes:
- 60 to 80 percent of Silicon Dioxide (SiO2)
- 10 to 25 percent of Boron Trioxide (B2O3)
- A small amount of Aluminum Oxide (Al2O3)

### Step 3: Determine the Chief Constituent
Among these components, Silicon Dioxide (SiO2) is present in the highest percentage (60 to 80%). Therefore, it is the most significant or chief constituent of Pyrex glass.

### Step 4: Conclusion
Based on the composition analysis, we conclude that the chief constituent of Pyrex glass is Silicon Dioxide (SiO2).

### Final Answer
The chief constituent of Pyrex glass is **Silicon Dioxide (SiO2)**.

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