Assertion (A): Amorphous solids possess a longrange order in the arrangement of their particles.
Reason (R): The formation of amorphous solids involves very rapid cooling.

Options

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is NOT the correct explanation of A
C. A is true but R is false
D. A is false and R is True

Explanation

To analyze the given assertion and reason, we will break down the statements and evaluate their validity step by step.

### Step 1: Understand the Assertion (A)
The assertion states: "Amorphous solids possess a long-range order in the arrangement of their particles."

- Amorphous solids are characterized by a lack of long-range order in their structure. Unlike crystalline solids, which have a regular and repeating arrangement of particles extending over long distances, amorphous solids have a disordered arrangement. Therefore, this assertion is **false**.

### Step 2: Understand the Reason (R)
The reason states: "The formation of amorphous solids involves very rapid cooling."

- This statement is **true**. Amorphous solids are formed when a liquid is cooled rapidly, preventing the particles from arranging themselves into a well-defined crystalline structure. This rapid cooling leads to a disordered arrangement typical of amorphous solids.

### Step 3: Evaluate the Relationship Between Assertion and Reason
Now we need to evaluate the relationship between the assertion and the reason:

- The assertion is false, while the reason is true. In logical terms, for the assertion to be valid, the reason must support it. Since the assertion is false and the reason is true, the two statements do not correlate in a way that supports the assertion.

### Conclusion
Based on the evaluation:
- Assertion (A) is false.
- Reason (R) is true.
- Therefore, the correct answer is that the assertion is false, and the reason is true.

### Final Answer
The answer is option 4: Assertion (A) is false, and Reason (R) is true.

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