A: Urethane on reaction with anmonia gives urea.
R: Formula of urethane is
`NH_(2)-overset(O)overset(||)C-NH-OCH_(2)CH_(3)`

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 solve the question, we need to analyze both the assertion (A) and the reason (R) provided in the question.

### Step 1: Understand the Assertion
The assertion states that "Urethane on reaction with ammonia gives urea."
- Urethane, also known as ethyl carbamate, has the structure:
\[ \text{NH}_2\text{CO}\text{NHOCH}_2\text{CH}_3 \]
- When urethane reacts with ammonia, it undergoes a reaction that produces urea and ethanol. The reaction can be represented as follows:
\[ \text{NH}_2\text{CO}\text{NHOCH}_2\text{CH}_3 + \text{NH}_3 \rightarrow \text{NH}_2\text{CO}\text{NH}_2 + \text{C}_2\text{H}_5\text{OH} \]
- The product urea has the formula:
\[ \text{NH}_2\text{CO}\text{NH}_2 \]
- Therefore, the assertion is **true**.

### Step 2: Understand the Reason
The reason states that "the formula of urethane is NH2-overset(O)overset(||)C-NH-OCH2CH3."
- The correct structure of urethane (ethyl carbamate) is:
\[ \text{NH}_2\text{CO}\text{NHOCH}_2\text{CH}_3 \]
- The formula given in the reason is not correctly formatted. The correct representation should clearly show the carbonyl (C=O) and the ethyl group (OCH2CH3) attached to the nitrogen.
- Therefore, the reason is **false**.

### Step 3: Conclusion
- Since the assertion is true and the reason is false, we conclude that the correct answer is option 3.

### Final Answer
The correct answer is option 3: Assertion is true, Reason is false.

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