CaO does not react with

Options

A. `SiO_2`
B. `P_4O_10`
C. `CO_2`
D. `MgO_2`

Answer

To determine what Calcium Oxide (CaO) does not react with, we need to analyze the nature of CaO and its reactivity with other oxides.

### Step-by-Step Solution:

1. **Identify the Nature of Calcium Oxide (CaO)**:
- Calcium Oxide is a metallic oxide, specifically a basic oxide. Basic oxides are typically formed from metals and react with acids to form salts and water.

2. **Understand the Reactivity of Basic Oxides**:
- Basic oxides, like CaO, generally react with acidic oxides to form salts. However, basic oxides do not react with each other.

3. **Identify Other Oxides**:
- We need to consider the nature of the other oxides mentioned in the question. For example:
- Silicon Oxide (SiO2) is an amphoteric oxide, meaning it can react with both acids and bases.
- Carbon Dioxide (CO2) is an acidic oxide and can react with basic oxides.
- Magnesium Oxide (MgO) is also a basic oxide.

4. **Determine Non-Reactive Pair**:
- Since both CaO and MgO are basic oxides, they will not react with each other. Therefore, the correct answer to the question is that Calcium Oxide does not react with Magnesium Oxide.

5. **Conclusion**:
- The final answer is that Calcium Oxide (CaO) does not react with Magnesium Oxide (MgO).

### Final Answer:
Calcium Oxide does not react with Magnesium Oxide.

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