Assertion (A): magnesium keeps on burning in `CO_(2)`.
Reason (R ): Magnesium reduces `CO_(2)` to `C`.

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.

Explanation

To analyze the assertion and reason provided in the question, we will break down the information step by step.

### Step 1: Understanding the Assertion
The assertion states that magnesium keeps burning in carbon dioxide (CO₂).

**Explanation**: Magnesium is a highly reactive metal that can react with carbon dioxide when heated. The reaction produces magnesium oxide (MgO) and carbon (C).

### Step 2: Writing the Reaction
The chemical reaction can be represented as follows:

\[ 2 \text{Mg} + \text{CO}_2 \rightarrow 2 \text{MgO} + \text{C} \]

**Explanation**: In this reaction, magnesium reacts with carbon dioxide to produce magnesium oxide and carbon.

### Step 3: Understanding the Reason
The reason states that magnesium reduces carbon dioxide to carbon.

**Explanation**: In the reaction, magnesium acts as a reducing agent. It donates electrons and reduces the carbon in carbon dioxide (which has a higher oxidation state) to elemental carbon (which has an oxidation state of zero).

### Step 4: Analyzing the Assertion and Reason
Both the assertion and the reason are true. The assertion is correct because magnesium does burn in carbon dioxide, and the reason is also correct because magnesium reduces carbon dioxide to carbon.

### Step 5: Conclusion
Since both the assertion and the reason are true, and the reason correctly explains the assertion, we conclude that the correct option is the one stating that both the assertion and reason are correct, and the reason is the correct explanation of the assertion.

### Final Answer
Both the assertion and the reason are correct, and the reason is the correct explanation of the assertion.

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