Question

explain starch hydrolysis with hcl

Answer 1

Starch is composed both of amylose and amylopectin - these are polymers of glucose, they just differ in their overall bonding. (look at the pictures attached).

An acetal bond (also called glycosidic bond) joins 2 glucose molecules together; the acid-catalyzed hydrolysis of an acetal bond begins by protonation of the O joining them, electrons from the oxygen form a double bond with the anomeric carbon breaking the C-O bond.





The unstable cation is attacked by (one of the lone pairs on) a water molecule at the anomeric carbon, reforming the glucose molecule and the acid.