A : Tailing of Hg caused by ozone is due to formation of HgO .
R : In the presence of `O_(3)` , Hg does not loses its meniscus .

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 (3)
D. If both Assertion and Reason are false statements , then mark (4)

Answer

To analyze the given statements, we will break down the assertion (A) and the reason (R) step by step.

### Step 1: Understand the Assertion (A)
The assertion states that the tailing of mercury (Hg) caused by ozone (O₃) is due to the formation of mercury oxide (HgO).

- **Explanation**: When ozone is introduced to mercury, a chemical reaction occurs where mercury reacts with ozone to form mercury oxide. This reaction is significant because it indicates that the presence of ozone can lead to the oxidation of mercury.

### Step 2: Understand the Reason (R)
The reason states that in the presence of ozone, mercury does not lose its meniscus.

- **Explanation**: The term "meniscus" refers to the curve at the surface of a liquid. In the context of mercury, it typically refers to the characteristic shape of mercury in a container. The reason suggests that even when ozone is present, the mercury retains its meniscus shape.

### Step 3: Analyze the Relationship between A and R
Now we need to determine whether the assertion and reason are true or false and if they are related.

- **Assertion (A)**: True. The formation of mercury oxide (HgO) does occur when mercury reacts with ozone.
- **Reason (R)**: False. In fact, when mercury reacts with ozone, it does lose its meniscus due to the formation of mercury oxide, which alters its physical properties.

### Step 4: Conclusion
Since the assertion is true and the reason is false, we conclude that the correct relationship is that A is true, and R is false.

### Final Answer
The assertion (A) is true, while the reason (R) is false.

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