A: Magnesium oxide is used for the lining in stoel making furnace .
R: Magnesium oxides acts as flux

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false, then mark
D. If both Assertion and Reason are false statements, then mark (4)

Answer

To analyze the given statement and reason, we can break it down into steps:

### Step 1: Understand the Statement (A)
- **Statement (A)**: "Magnesium oxide is used for the lining in steel making furnace."
- **Explanation**: Magnesium oxide (MgO) is indeed used as a lining material in steel-making furnaces. This is because it can withstand high temperatures and is resistant to the corrosive nature of molten metals.

### Step 2: Understand the Reason (R)
- **Reason (R)**: "Magnesium oxide acts as flux."
- **Explanation**: In metallurgy, a flux is a substance that helps to remove impurities from metals during the smelting process. Magnesium oxide can combine with impurities to form a slag, which can be easily removed, thus facilitating the purification of the metal.

### Step 3: Establish the Connection
- **Connection**: The use of magnesium oxide as a lining in steel-making furnaces is directly related to its property as a flux. By acting as a flux, it helps in the purification process of steel, making it an ideal material for furnace linings.

### Step 4: Conclusion
- Since the statement (A) is true and the reason (R) correctly explains why magnesium oxide is used in this context, we can conclude that both the statement and the reason are correct and that the reason is a valid explanation for the statement.

### Final Answer:
Both A and R are true, and R is the correct explanation of A.

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