




To determine the correct structure of L-fructose, we must understand the stereochemistry and structure of sugars, particularly their D and L configurations.
Fructose is a ketohexose, meaning it has a ketone group at the second carbon and has six carbon atoms. The difference between D-fructose and L-fructose lies in the configuration of the asymmetric carbon atoms, specifically the chiral centers.
The D/L notation does not refer to the direct spatial arrangement (dextrorotatory or levorotatory) but rather to the stereochemistry, which relates to the structure of glyceraldehyde. In sugars, the D or L configuration is determined by the orientation of the hydroxyl group on the last chiral carbon (farthest from the ketone group) in the Fischer projection:
For L-fructose, the hydroxyl group on the last chiral carbon should be on the left in its Fischer projection.
Let's examine the given options to identify the correct structure of L-fructose:
The correct image, showing the hydroxyl group on the last chiral carbon of L-fructose positioned to the left, matches the structure in the third option:
Therefore, the correct structure for L-fructose is represented by the third option. This aligns with the characteristic organization of L-sugars.
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)

Cobalt chloride when dissolved in water forms pink colored complex $X$ which has octahedral geometry. This solution on treating with cone $HCl$ forms deep blue complex, $\underline{Y}$ which has a $\underline{Z}$ geometry $X, Y$ and $Z$, respectively, are
Number of compounds among the following which contain sulfur as a heteroatom is ___.
Compounds: Furan, Thiophene, Pyridine, Pyrrole, Cysteine, Tyrosine
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)