Robert Griffiths age 17, of Shelbyville, 'Ind
What are electrons?
Solids, liquids and gases are forms of matter made from atoms and the atoms themselves are made of smaller particles, We know of some two dozen different atomic particles and more may be discovered. The three basic particles are protons charged with positive electricity, electron charged with negative electricity and neutrons which are electrically neutral. The nature of an atom, say, of oxygen or tin depends entirely upon the number of its particles. But all protons are alike and the 29 electrons of a copper atom are just like every other electron in the universe.
A proton is slightly lighter than a neutron and 1,836 times heavier than an electron. But its positive charge exactly balances the negative charge of the electron. A positive and negative charge attract each other and become electrically neutral. Two negative charges repel each other a$ do two positive charges. Two electrons pressed together have the energy of a tiny coiled spring. Some of the electronts energy comes from this fact and some from its place in the structure of the atom.
The protons and the neutrons are securely locked in the nucleus of the atom, The electrons swarm around the nucleus like flies around a lamp and most of the atom is empty space. In a normal atom, the number of protons equals the number of electrons and the electrons are arranged in orderly shells about the nucleus. The inner shell is complete with two, the second with eight and the third with 18 electrons. It takes a big jolt to shake loose the electrons in a completed shell. But an outer shell is restless to complete itself by sharing electrons with atoms from other elements.
The copper atom has 29 electrons, three completed shells and a lone lone electron in a fourth shell, In a lump of copper these/electrons tend to hop restlessly from atom to atom. Voltage, a jolt of electrical pressure, sends these electrons hopping through a wire circuit in the same direction and their combined energy gives us electrical current, It takes about three billion, billion electrons, jogging back and forth through a filament 60 times a second, to keep a reading lamp burning.
The energy of the electron is used to form and reform compounds from basic elements. An atom of oxygen has eight electrons, with two vacancies in its second shell. It tries to complete this shell by teaming up to share electrons with atoms of other elements. An atom of hydrogen has‑‑but one electron. Under certain conditions an atom of oxygen borrows the electrons from two atoms of hydrogen and the three atoms together form a particle of the compound which is water.
Salt, sugar, carbon dioxide and countless compounds around us are formed from units of atoms held together by the energy in their electrons. The electrical energy in the tiny electron runs our toaster, lights our lamps and puts the picture on our TV screens. Yet the number of these busy little particles in a pound is two, followed by 30 zeroes.