Question

why are ionic comounds usually have high melting points

Answer 1

Because ionic bond having transfer of elctrons one atom to another atom ,only metal to non-metal . they are good condutor of electricity and their electron held together a strong elctrosatics force.

Answer 2

hey there!! 
here's ya answer :-

ionic compounds usually have high melting point because  in ionic compounds ,cations and anions are held together by strong electrostatic forces of attraction  hence large amounts of energy is required to overcome these forces . hence they have high melting points.

hope it helps ya