Explore the particles that make up atoms: protons, electrons, and electrons.

This lesson will explain that protons are positively charged particles having a mass of one amu and are found in the nucleus of the atom. It is 2 of 3 in the series titled "Subatomic Particles: The Proton."

A look at the reaction that fuels the Sun with this diagram of the nuclear fusion process.

This is a very detailed site containing information on several sub-atomic particles including the Hadron.

Slideshow looking at the history of models of the atom, including those proposed by John Dalton, J.J. Thomson, Ernest Rutherford, Niels Bohr, and James Chadwick. Discusses subatomic particles, including the numbers of protons, neutrons,...

Learn what atomic number is, and what happens if the numbers of protons in an atom changes.

This lesson will illustrate that an atom is mostly empty space and has a positively charged, massive core (containing both protons and neutrons called the nucleus) surrounded by negatively charged electrons. It is 2 of 3 in the series...

Learn about color change and pH as it relates to chemical changes.

Collapsed stars, between white dwarfs and black holes, can be studied as quark-gluon masses, or quark-hyperon groups. Extreme pressures lead to extreme states.

This lesson will define an isotope and explain what happens if the number of neutrons in an atom changes. It is 9 of 9 in the series titled "Isotopes."

This lesson will introduce the subatomic particles and explain where they are located and how they interact. It is 3 of 7 in the series titled "Subatomic Particles."

This lesson will introduce the subatomic particles and explain where they are located and how they interact. It is 7 of 7 in the series titled "Subatomic Particles."

This lesson will explain that electrons are negatively charged particles with negligible mass and are found in pairs in orbitals surrounding the nucleus of an atom. It is 3 of 3 in the series titled "Subatomic Particles: The Electron."

This lesson will provide an understanding of the basic chemistry of atoms. It is 4 of 5 in the series titled "Atoms."

This lesson will provide an understanding of the basic chemistry of atoms. It is 5 of 5 in the series titled "Atoms."

This lesson will explain that neutrons are particles in the nucleus that have no charge and a mass of one amu. It is 2 of 3 in the series titled "Subatomic Particles: The Neutron."

This animation discusses electrons and the properties of electrons in a storybook format featuring hairy monsters, strange rocks, and fun animations.

From CERN, the world's largest particle accelerator, this site contains a description of the Proton Synchotron, a device used to accelerate protons for use in other machines in the accelerator complex.

From CERN, the world's largest particle accelerator, this site contains a description of the Proton Synchotron, a device used to accelerate protons for use in other machines in the accelerator complex.

A look at the transition metal unununium, which was renamed roentgenium in 2004. Includes basic information, including symbol, number, mass, melting and boiling points, and numbers of protons, electron, and neutrons.

The experiments of Columbia University physicists (left to right) Chien-shiung Wu (1912-1997), Y.K. Lee, and L.W. Mo confirmed the theory of conservation of vector current. In the experiments, which took several months to complete,...

This is a simple picture of a hydrogen atom using the Bohr model. A negatively charged electron can be seen on the outside of the positively charged proton.

This diagram shows a basic atom structure with an atom core, proton, neutron and electron.

The three basic particles that make up atoms are defined and illustrated.