Structure of the Atom

Element symbols Elements are represented by either one capital letter or one capital letter and one lower case letter. This system is used throughout the world so scientists can communicate.

Element Symbols The letters chosen to represent an element are sometimes taken from its name, to honor scientists, after a place or for one of the element’s properties. The symbol for silver, Ag, is taken from its Latin name, Argentum.

Elements of the periodic table

Atomic Structure An element is matter that is composed solely of one type of atom. An atom consists of protons, neutron and electrons. The protons and neutrons are found in the nucleus. The electrons are found in a cloud surrounding the nucleus.

Charges Protons have a positive charge. Neutrons have a neutral charge. These two particles make up the nucleus, so the overall charge of the nucleus is positive. The electrons have a negative charge and surround the nucleus.

Quarks Electrons are among the simplest particles. Scientists have speculated for years that both protons and neutrons are composed of smaller particles, called quarks. We now know of 6 quarks, named up, down, top, bottom, strange and charm. Scientists believe that protons and neutrons are each composed of 3 quarks. The study of quarks is recent and on-going.

Quarks

Particle Accelerator A particle accelerator is used to accelerate particles (protons and neutrons) and slam them together. This is how quarks were discovered and how we study them today.

The Fermi National Accelerator Laboratory. Particle accelerator The Fermi National Accelerator Laboratory.

What are quarks?

Electron Cloud Model The currently accepted atomic model is known as the electron cloud model.

Scientists who Contributed to Atomic theory