Glucose and fructose are

Options

A. anomers
B. epimers
C. diastercomers
D. functional isomers

Answer

D

Explanation

Both have the same molecular formula `(C_(6) H_(12) O_(6))` but glucose is an aldohexose while fructose is a 2- ketohexose. Both gives a positive test with Tollen's reagent (formation of a shiny silver mirror), Fehling's solution (discharge of the blue colour and the formation of a red ppt. of `Cu_(2) O`) and Benedict's solution (same changes as with Fehling's solution). The keto sugar reacts because it rearranges to an aldosugar under the basic conditions.
The ketose and the aldose tautomerize in `OH^(-)` (from aq `NaOH)` to a common intermediate enediol, esbablishing the equilibrium,
Only the aldosugar reacts with `Br_(2) // H_(2) O`, a positive test is indicated by loss of the orange colour of the aqueous `Br_(2)` solution,
Anomers are epimers whose configuration differ only about the `C1`