Discover the history, structure, and importance of the periodic table of elements, from Mendeleev’s discovery to modern scientific applications. When you purchase through links on our site, we may ...

An element is defined according to the number of protons contained inside the nucleus of each atom. No two elements have the same number of protons, hence each element has a unique atomic number. The ...

Protons are tiny particles just a femtometer across, but without them, atoms wouldn't exist. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.

There are scientific explanations for this, including theories about layers of particles in the nucleus, and “magic numbers” of protons and neutrons that may be stable in combination. If we can find ...