Practical Organic Chemistry and PurificationhardMCQ SINGLE⭐ Must-Do

Which of the following compounds is a known JEE exception that gives a false-positive green flame inPractical Organic Chemistry and Purification Chemistry Question

Question

Which of the following compounds is a known JEE exception that gives a false-positive green flame in the Beilstein test despite containing no halogens?

Answer: B

💡 Solution & Explanation

Urea and thiourea can form volatile copper cyanides upon strong heating, which impart a green/blue flame identical to volatile copper halides, causing a false positive.

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