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Because fingerprints are unique to an individual (even between identical twins), they are useful information in forensic situations. To make fingerprints visible, various chemistry can be used. Cyanoacrylate fumes are

the most common method of developing fingerprints, turning them white. a) One such compound is ethyl cyanoacrylate, which can be synthesized as below. Propose a mechanism for the reaction, identifying the driving force for the reaction.[4] b) Propose a mechanism for the dimerisation of ethyl cyanoacrylate, which will also involve the incorporation of water. If the pi bond is a nucleophile, use acid catalysis; if it is an electrophile, use base catalysis.14] Ninhydrin, reacting with amino acids present, produces a compound with a purple colour that makes the finger prints visible. c) Propose a mechanism for either Step 1or Step 4. d) Propose a mechanism for Step 2, identifying the structure of J. e) Propose a mechanism for Step 3, identifying the structure of Q.

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