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Which of the following rubbers when treated with trichloroacetic acid give pink-mauve melt and on dilution give grey-mauve precipitate?

Which of the following rubbers when treated with trichloroacetic acid give pink-mauve melt and on dilution give grey-mauve precipitate? Correct Answer all of the mentioned

Acetone-extracted NR, isomerizaed rubber and gutta percha when warmed with trichloroacetic acid give pink-mauve melt and on dilution with water result in grey-mauve precipitate.

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