Refractory materials are used in furnace because they

Options

A. possess great structural strength
B. can withstand high temperature
C. are chemically inser
D. do not require replacement

Explanation

**Step-by-Step Solution:**

1. **Understanding Refractory Materials:**
- Refractory materials are substances that are resistant to decomposition by heat, pressure, or chemical attack. They are typically used in high-temperature environments such as furnaces.

2. **Identifying Properties of Refractory Materials:**
- The key properties that make refractory materials suitable for furnace construction include:
- High melting point
- Ability to withstand high temperatures without deforming
- Chemical inertness, meaning they do not react with other materials at high temperatures

3. **Analyzing the Options:**
- Option 1: "Possess great structural strength" - While structural strength is important, it is not the primary reason for using refractory materials in furnaces.
- Option 2: "Can withstand high temperature" - This is a significant characteristic of refractory materials, making this option correct.
- Option 3: "Are chemically inert" - This property is also crucial as it prevents reactions that could compromise the furnace's integrity, making this option correct as well.
- Option 4: "Do not require replacement" - This is not entirely accurate as refractory materials can wear out and may need replacement over time.

4. **Conclusion:**
- Based on the analysis, the correct answers are:
- Option 2: "Can withstand high temperature"
- Option 3: "Are chemically inert"

**Final Answer:**
Refractory materials are used in furnaces primarily because they can withstand high temperatures and are chemically inert.

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