Question

A compound which does not give positive test for nitrogen is:

• A. urea
• B. azobenzene
• C. glycine
• D. phenyl hydrazine

Answer 1

Based on standard chemical knowledge and the principles of Lassaigne's test for nitrogen, all the given compounds (urea, azobenzene, glycine, and phenyl hydrazine) contain both carbon and nitrogen and should give a positive test for nitrogen. There is a strong indication that the question or the provided options are flawed, as none of the options should give a negative test for nitrogen under standard Lassaigne's test conditions.

However, if we are forced to choose an answer from the given options, and assuming there is a hidden reason or a less common exception, we cannot provide a scientifically justified solution. Given the conflict with fundamental chemistry principles, providing a definitive answer from the options is not possible without further clarification or correction of the question.

Answer 2

Based on standard chemical knowledge and the principles of Lassaigne's test for nitrogen, all the given compounds (urea, azobenzene, glycine, and phenyl hydrazine) contain both carbon and nitrogen and should give a positive test for nitrogen. There is a strong indication that the question or the provided options are flawed, as none of the options should give a negative test for nitrogen under standard Lassaigne's test conditions.

However, if we are forced to choose an answer from the given options, and assuming there is a hidden reason or a less common exception, we cannot provide a scientifically justified solution. Given the conflict with fundamental chemistry principles, providing a definitive answer from the options is not possible without further clarification or correction of the question.