# Why is chitin ordinarily insoluble in water, but soluble after deacetylation? [closed]

Chitin is usually insoluble in water. How does its chemical structure explain this?

Furthermore, when chitin undergoes deacetylation, it becomes soluble and forms hydrogen bonds with water. How is this so?

The structure of chitin, an extended ribbon, is identical to that of cellulose, except that the $\ce{-OH}$ group on each C-2 is replaced by $\ce{-NHCOCH3}$, so the repeating units are N-acetyl-D-glucosamines in β (1→4) linkage.