Q. Assertion :When the ketohexose, D() fructose is treated with phenyl hydrazine it produces an osazone that is identical with the one prepared from either D-(+) glucose or D-(+) mannose. Reason: Sugars forming same osazone have different configuration C1 and C2 that are involved in osazone formation, the rest four carbon atoms (C3,C4,C5andC6 are same) are identical. Since all belongs to D-Family hence the configuration of last but one asymmetric carbon atom would be the same
