Why are alpha particles positive?

1 Answer
Dec 29, 2014

An alpha particles is positively charged because it is essentially the nucleus of a Helium-4 atom.

![http://education.jlab.org/glossary/http://alphaparticle.html](https://useruploads.socratic.org/9EZGKROShqR30xfsCF1g_alphaparticle.gif)

A Helium-4 nucleus is composed of two protons, which are positively charged particles, and two neutrons, which have no electric charge.

A neutral He atom has a mass of four units (2 protons + 2 neutrons) and a net charge of zero because it has two electrons that balance the protons' positive charge; since an alpha"-particle" only has the protons and the neutrons, its charge will be +2->+1 from each proton.