Assertion (A): Calcium and magnesium oxides are not reduced by carbon.
Reason (R ): Calcium and magnesium oxides react with carbon to form their respected carbides.

Options

A. If both `(A)` and `(R )` are correct and `(R )` is the correct explanation of `(A)`.
B. If both `(A)` and `(R )` are correct, but `(R )` is not the correct explanation of `(A)`.
C. If `(A)` is correct, but `(R )` is incorrect.
D. If `(A)` is incrrect, but `(R )` is correct.

Answer

To analyze the given assertion and reason, let's break down the statements step by step.

### Step 1: Analyze the Assertion (A)
The assertion states that "Calcium and magnesium oxides are not reduced by carbon."

- **Explanation**: In general, the oxides of alkaline earth metals (like calcium and magnesium) are quite stable and require a more reactive reducing agent than carbon to be reduced. Therefore, this assertion is **true**.

### Step 2: Analyze the Reason (R)
The reason states that "Calcium and magnesium oxides react with carbon to form their respective carbides."

- **Explanation**: When calcium oxide (CaO) reacts with carbon, it can indeed form calcium carbide (CaC2) along with carbon monoxide (CO). Similarly, magnesium oxide (MgO) can also react with carbon to form magnesium carbide (MgC2). Thus, this statement is also **true**.

### Step 3: Determine the Relationship Between Assertion and Reason
Now we need to determine whether the reason correctly explains the assertion.

- While both statements are true, the reason does not provide a valid explanation for the assertion. The assertion claims that calcium and magnesium oxides are not reduced by carbon, while the reason suggests a reaction that leads to the formation of carbides. The formation of carbides does not imply that the oxides are reduced; rather, it indicates a different type of reaction.

### Conclusion
- The assertion (A) is true: Calcium and magnesium oxides are not reduced by carbon.
- The reason (R) is true: Calcium and magnesium oxides can react with carbon to form carbides.
- However, the reason does not explain the assertion.

Thus, the correct answer is that the assertion is true, the reason is true, but the reason is not a correct explanation of the assertion.

### Final Answer
Both the assertion and reason are true, but the reason is not a correct explanation for the assertion.

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