>>136405921There are things called anti-protons, anti-neutrons, and anti-protons, basically the same stuff but with opposite charges (anti-protons are negative and anti-electrons are positive)
Anti-hydrogen can be synthesized in a lab and be stable, but because anti-particle can't be held in normal matter containers, they explode very quickly and the anti-protons attract to the protons, being oppisite charges, and the same with the electrons, canceling out into an explosion of radiation
It'd be water, but it'd probably explode as soon as the cup was filled with the stuff.