β-D-glucopyranose in the chair form is the most widely occurring form of glucose in nature and it has the following characteristics EXCEPT:
A) forms a six-membered ring.
B) carbon 6 is above the plane of the chair.
C) all of the −OH groups are equatorial.
D) the anomeric carbon has a hydroxyl that is below the plane of the chair.
E) all axial positions are occupied by −H.

Question

Quizplus · Accepted Answer

The hydroxyl group on the anomeric carbon in the chair form of β-D-glucopyranose is above the plane of the chair, not below as stated in option D. This is because the anomeric carbon is attached to both an oxygen atom from the ring and a hydroxyl group, and it adopts a tetrahedral configuration with the hydroxyl group in an axial position and the ring oxygen in an equatorial position.

β-D-Glucopyranose in the Chair Form Is the Most Widely Occurring