Assertion : The H-bond present in `NH_(3)` dissolved in water is best represented by : `H-underset(|)underset(H)(N)-H--underset(|)underset(H)(O)-H` and not by `H-underset(|)underset(H)overset(|)overset(H)(N)---underset(|)underset(H)(H)-O`
Reason : The `O-H` bond polarity is more compared to that `N-H` bond.

Options

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

Explanation

To solve the given question, we need to analyze both the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states that the hydrogen bond present in ammonia (NH₃) dissolved in water is best represented by the structure:

`H-underset(|)underset(H)(N)-H--underset(|)underset(H)(O)-H`

This representation indicates a hydrogen bond between the nitrogen (N) in ammonia and the oxygen (O) in water.

### Step 2: Analyze the Alternative Representation
The alternative representation given is:

`H-underset(|)underset(H)overset(|)overset(H)(N)---underset(|)underset(H)(H)-O`

In this structure, it suggests a hydrogen bond between the nitrogen (N) in ammonia and the hydrogen (H) in water.

### Step 3: Compare Bond Polarities
To determine which representation is correct, we must consider the bond polarities:
- The O-H bond in water is more polar than the N-H bond in ammonia. This is due to the higher electronegativity of oxygen compared to nitrogen.
- A more polar bond leads to stronger hydrogen bonding.

### Step 4: Conclusion on the Assertion
Since the O-H bond is more polar than the N-H bond, the hydrogen bond formed between the O in water and the H in NH₃ is stronger than the bond formed between N and H. Therefore, the assertion that the first representation is the best representation of the hydrogen bond is incorrect.

### Step 5: Analyze the Reason
The reason states that the O-H bond polarity is greater compared to the N-H bond. This statement is correct as we have established that oxygen is more electronegative than nitrogen, leading to a stronger O-H bond.

### Final Conclusion
- **Assertion**: Incorrect
- **Reason**: Correct

### Summary
The correct answer is that the assertion is incorrect while the reason is correct.

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