What is an Electron?

What is an Electron?  I guess the questions we need to ask first are:  What is an atom? & What are atoms made of?  Atoms are the basic building blocks of ordinary matter.  Atoms can join together to form molecules, which in turn form all of the objects around us.  Atoms are composed of particles called protons, electrons and neutrons.  Protons carry a positive electrical charge, electrons carry a negative electrical charge and neutrons carry no electrical charge at all.  The protons and neutrons cluster together in the central part of the atom, called the nucleus, and the electrons 'orbit' the nucleus.  A particular atom will have the same number of protons and electrons and most atoms have at least as many neutrons as protons.
Now that we have some background on the atom we can look closer on one of it elements - the electron.  The electron is a subatomic particle carrying a negative electric charge.  It has no known components or substructure.  Therefore the electron is generally-believed to be an elementary particle.  An electron has a mass that is approximately 1/1836 that of the proton, and each one carries a charge of 1.6 x 10-19 coulombs.  The Coulomb force is the basis for the ability of a positively charged nucleus to "hold onto" electrons and get them to form the electron cloud that generally defines the volume of the atom.  As stated earlier, electrons, together with atomic nuclei made of protons and neutrons, make up atoms.  However, electrons contribute less than 0.06% to an atom's total mass.  When we watch the TV show Star Trek we here that one of the characters named  "Data" has a positronic brain.  One of the reasons that the show is so popular is because the terminology used is based on real world concepts.  It turns out that there is an element called a positron, it is the antiparticle of the electron, which is identical to the electron except that it carries electrical and other charges of the opposite sign, it is also referred to as an anti-electron or anti-matter (another term used greatly on Star Trek).  When an electron collides with a positron, both particles may either scatter off each other or be totally annihilated, producing a pair (or more) of gamma ray photons. 

Electrons, like all matter, have quantum mechanical properties of both a particle and a wave, so they can collide with other particles and be diffracted like light.  In an atom, electronic configuration refers to the number of electrons in each electron shell.  There can be up to 2 electrons in the first shell, 8 in the second and third and then 18 in the fourth.  You can work out the electronic configuration by looking at the periodic table, by looking at the rows you know how many shells there are and by looking at the columns you know the number of valance electrons (number of electrons in the outer shell).  Another fact to notes is that when electrons change energy levels (shifting orbitals), they do so by absorbing a quantum of light (to move "out") or releasing a quantum of light (to move "in"), when (moving "in") electrons radiate energy in the form of photons.  The electrons of different types of atoms have different degrees of freedom to move around.  With some types of materials, such as metals, the outermost electrons in the atoms are so loosely bound that they chaotically move in the space between the atoms of that material by nothing more than the influence of room-temperature heat energy. Because these virtually unbound electrons are free to leave their respective atoms and float around in the space between adjacent atoms, they are often called free electrons. In other types of materials such as glass, the atoms' electrons have very little freedom to move around.  While external forces such as physical rubbing can force some of these electrons to leave their respective atoms and transfer to the atoms of another material, they do not move between atoms within that material very easily.  This relative mobility of electrons within a material is known as electric conductivity.  Conductivity is determined by the types of atoms in a material and how the atoms are linked together with one another. Materials with high electron mobility (many free electrons) are called conductors, while materials with low electron mobility (few or no free electrons) are called insulators. 

Electron current flow is not the entry into a conductor of an electron and the exiting of that electron from the other end.  Rather, it is the entry of an electron into one end of a conductor and then the "appearance" of an electron from the other end of the conductor.  As each electron moves uniformly through a conductor, it pushes on the one ahead of it, such that all the electrons move together as a group.  The starting and stopping of electron flow through the length of a conductive path is virtually instantaneous from one end of a conductor to the other, even though the motion of each electron may be very slow.  An approximate analogy is that of a tube filled end-to-end with ball-bearings: The tube is full of ball-bearings, just as a conductor is full of free electrons ready to be moved by an outside influence. If a single ball-bearing is suddenly inserted into this full tube on the left-hand side, another ball-bearing will immediately try to exit the tube on the right.  Even though each ball-bearing only traveled a short distance, the transfer of motion through the tube is virtually instantaneous from the left end to the right end, no matter how long the tube is. With electricity, the overall effect from one end of a conductor to the other happens at the speed of light: a swift 186,000 miles per second!  Each individual electron, though, travels through the conductor at a much slower pace. 

In many physical phenomena, such as electricity, magnetism, and thermal conductivity, electrons play an essential role.  Electrons are used in many applications, including welding, cathode ray tubes, electron microscopes, radiation therapy, lasers and particle accelerators. The study of electrons, electric fields, magnetic fields and the particles that they interact with can be studied more in the following branches of physics: classical mechanics, electromagnetism, and quantum mechanics.  

Lowest Prices on Electronics!

Cash for Electronic Scrap

contact lens - Find the contacts you need at a discount price from Just Lenses. Contact lenses for less right to your door.
readers glasses - Eye Topics - News, reviews and FAQs about reading glasses. Find out everything you need to know before you buy. Browse by manufacturers and types.
prescription glasses on line - features eyeglasses prices from array of brands, including Adidas, Savvy, Marc Jacobs, and Versace eyeglasses. Easy to browse and compare prices.
chicago homes for sale - 123 Chicago Real Estate is effortlessly the most useful Chicago real estate website for listings to buy or sell Chicago homes, condos and lofts.

Ideas for Life

Buy Televisions at

Huge selection of cool gadgets at wholesale prices.

Need TV or Monitor Repair? Submit the form below and details will be sent to you for expert and guaranteed repair service.


Name *

Email Address *