Question

How many chiral carbon atoms are there in the open-chain form of glucose?

Answer 1

Chiral carbons in glucose:

• A carbon atom attached to four different atoms or groups of atoms is known as chiral carbon.
• The molecular formula of Glucose is ${\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6$
• The structure of glucose has one aldehyde group at any end of the carbon chain in the open-chain form of glucose.

• The first and sixth Carbon is attached to two same hydrogen atoms hence it is not a chiral atom.
• The second, third, fourth, and fifth are attached to four different groups hence it is a chiral carbon atom.
• The glucose molecule can exist as an open straight chain as well as in ring form.
• The open straight chain of Glucose is an open and unbranched backbone of six carbon.
• In the First Carbon, the aldehyde group($\mathrm{CHO}$) is present, in the sixth carbon Hydroxyl ($\mathrm{OH}$) group is present and the remaining valencies of carbon are satisfied by hydrogen atoms.

Hence, there are four chiral carbon atoms in the open-chain form of glucose.