Assertion. `HNO_(3)` renders iron passive.
Reason. Iron reacts with `HNO_(3)` to form ferric nitrate.

Options

A. If both assertion and reason are true, and reason is the correct explanation of the assertion.
B. If both assertion and reason are ture, but reason is not the correct explanantion of the assertion.
C. If assertion is true, but reason is false.
D. If both assertion and reason are false

Explanation

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

### Step 1: Understanding the Assertion
The assertion states that "HNO₃ renders iron passive."
- **Passive** means that the metal (iron, in this case) does not react with other substances as it normally would. This is often due to the formation of a protective layer on the metal's surface.

### Step 2: Understanding the Reason
The reason states that "Iron reacts with HNO₃ to form ferric nitrate."
- When iron (Fe) reacts with nitric acid (HNO₃), it does indeed form ferric nitrate (Fe(NO₃)₃) along with nitrogen oxides (NO or NO₂) depending on the concentration of the acid.

### Step 3: The Reaction Mechanism
- When iron is exposed to HNO₃, it can form a layer of iron oxide or ferric oxide (Fe₂O₃) on its surface. This oxide layer acts as a barrier, preventing further reaction of iron with the acid and thus rendering it passive.

### Step 4: Conclusion
- Therefore, the assertion is true because HNO₃ does render iron passive by forming a protective oxide layer. The reason is also true since iron does react with HNO₃ to form ferric nitrate, which is part of the process that leads to passivation.

### Final Answer
Both the assertion and the reason are true, and the reason correctly explains the assertion.

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