What do you mean by D- and L-glucose? State the relationship between D and L sign with nature of optical rotations.

Explanation

First part: D- and L-configurations are asigned on the basis of the configuration of the glucose molecule. If the `-HO` group on the C-5 lies towards the right hand side, it is called as D-glucose whereas if the `-OH` group is on the left side, then it is termed as L-glucose.
Second part: D- and L-glucose are a pair of enantiomers. They are mirror images of each other.