Proton (noun, “PRO-tahn”)
A proton is a particle with a positive electric charge. It is one of the three types of particles that make up atoms. Along with neutrons, protons form an atom’s core, or nucleus. That nucleus is surrounded by a cloud of electrons. The electrons’ negative charge makes them attracted to the positive protons in the nucleus.
The number of protons in an atom determines what element it is. Oxygen, for instance, has eight protons while gold has 79. Atoms of the same element can have different numbers of neutrons. Those different varieties of an atom are called isotopes. And atoms of the same element can gain or lose electrons. When that happens, they become ions of that element. But when atoms gain or lose protons, they become wholly different elements. A single proton more, for instance, is the difference between platinum and gold.
Protons may be tiny, but they still can be broken down into even smaller bits of matter. Those bits are called quarks. Each proton is made of two “up” quarks and a “down” quark. Particles made of quarks, including protons as well as neutrons, are called hadrons.
In a sentence
Acids are molecules that are good at giving away protons, while bases are good at snatching protons up.