Question

what is tautomerism give explanation

Answer 1

migration of hydrogen from carbon to oxygen is called as tautomerism.
example. keto enol tautomerism
CH3COCH3 <=> CH2=CH (OH) CH3
Reactant is ketone and product is en+ol... hence it is keto enol tautomerism

Answer 2

Tautomerism :- Compounds having same molecular formula but differ in position of Hydrogen atom and are in equilibrium. Eg:- Acetone (also called as Ketos), enol.