The ionic compounds have a high melting point because the ionic bond consists in the donation of the electrons from the metallic ion to the non-metallic ion due to the difference in electronegativity. Because of this, the ion core of the elements of this compounds are very close to each other, having a strong bond between all the speciements, therefore elevating the melting point.
When a boy throws a ball and accidentally breaks a window, the momentum of the ball and all the pieces of glass taken together after the collision is THE SAME as the momentum of the ball before the collision
