They may be readily fused and volatilized with their melting and boiling points becoming lower with increasing atomic mass . They are the strongest electropositive metals. These elements react vigorously, even violently with water. In the case of antineutrons they are opposite of neutrons in magnetic moment. Positrons , which are the counterpart to electrons , have a positive charge and antiprotons have a negative charge.
Photons are their own antimatter counterpart.
When a particle of matter collides with a particle of antimatter, both particles are destroyed and their masses are converted to photons of equivalent energy. Number Search the Web.