Hello Readers friends , Did you know? Every tool we use today contains an electric charge, so every day we will always use a tool that is electrically charged. In fact, electric charge is one of the electric charges in the human body.
When talking about electric charge, there must always be a negative charge and a positive charge because without it the charge will create a repulsive force. In other words, charges with the same charge will cause a repulsive force and charges with a different charge will cause an attractive force.
Basically, elementary charge has interconnected particles, namely protons and electrons, both of which are part of the particles that make up the atom. However, in an electric charge, there are no neutrons. If there is no charge, current cannot flow.
The negatively charged part of the atom is the electron. These electrons are an important and often discussed part of the theory of the two sciences. In chemistry, electrons play an important role in the properties of electrolytes, namely the parts that affect the flow of electricity.
Because of its very important role, you must know and understand electrons as a basic science before studying other higher sciences. For more details, it’s a good idea to listen to the following reviews.
Definition of Electron
Electrons are subatomic particles with a negative charge and are often written as e-. Electrons have no known basic components or substructures, so they are said to be elementary particles. An electron has a mass of 1/1836 a proton. The intrinsic angular momentum (spin) of the electron is half its integer value in units, meaning it is a fermion.
The antiparticle of the electron is called the positron, which is like the electron but has a positive charge. When an electron collides with a positron, the two can scatter or be completely annihilated, creating a pair (or more) of gamma photons.
Electrons, belonging to the first generation of the lepton family, participate in gravitational, electromagnetic and weak interactions. Like all matter, electrons have both particle and wave properties (wave-particle duality), so they can collide with other particles and be diffracted like light. Since electrons belong to fermions, two different electrons cannot occupy the same quantum state according to the Pauli exclusion principle.
The concept of indivisible charges natural philosopher Richard Laming theorized to explain the chemical properties of atoms in 1838; [6] The name electron was given to describe this charge in 1894 by the Irish physicist George Johnstone Stoney . The electron was identified as a particle in 1897 by JJ Thomson .
In many physical phenomena, such as electricity, magnetism and thermal conduction, electrons play a very important role. An electron moving relative to an observer will generate a magnetic field and the path of the electron will also be deflected by the external magnetic field. When an electron is accelerated, it can absorb or emit energy in the form of photons.
Electrons and atomic nuclei are made up of the protons and neutrons that make up the atom. However, electrons make up only 0.06% of the total atomic mass. The Coulomb attraction between electrons and protons causes electrons to bond within the atom. The exchange or sharing of electrons between two or more atoms is the main cause of chemical bonds.
Theoretically, most electrons in the universe were generated in the Big Bang, but they can also be generated by the beta decay of radioactive isotopes as well as in high energetic collisions, such as when cosmic rays enter the atmosphere.
Electrons can be destroyed by destroying a positron, or they can be absorbed during stellar nucleosynthesis. Modern experimental equipment can be used to charge or monitor individual electrons. Electrons have many applications in modern technology, for example in electron microscopy, radiation therapy and particle accelerators.
Electron History
The ancient Greeks noticed that amber attracted small objects when rubbed with animal hair. Apart from lightning, this phenomenon is one of the earliest human records regarding electricity. In his 1600 work De Magnete, English physicist William Gilbert coined the new term electricus to refer to the attracting property of small objects after being rubbed. The English word for electric is derived from the Latin ēlectrum , which comes from the Greek ήλεκτρον (ēlektron) for amber.
In 1737, CF Du Fay and Hawksbee independently discovered what they believed to be two types of triboelectricity; one is produced by scrubbing glass, the other is produced by scrubbing plastic. From this, Du Fay hypothesized that electricity consists of two electrical fluids, namely “glass” and “plastic”, which are separated by friction and neutralize each other when combined.
A decade later, Benjamin Franklin proposed that electricity did not come from different electrical fluids, but from the same electrolytic fluid under different pressures. He gave a nomenclature of positive and negative charges for these different pressures.
Between 1838 and 1851, English naturalist Richard Laming developed the idea that the atom consisted of a core of matter surrounded by electrically charged subatomic particles. As early as 1846, the German physicist William Weber hypothesized that electricity consists of positively and negatively charged fluids, and their interaction obeys the inverse square law.
After studying electrolysis in 1874, Irish physicist George Johnstone Stoney theorized that there was a “definite unit of electric charge” which was the divalent ionic charge. He succeeded in estimating the value of this elementary charge e thanks to Faraday’s laws of electrolysis. However, Stoney believed that this charge was permanently attached to the atom and could not be removed. In 1881, the German physicist Hermann von Helmholtz proposed that positive and negative charges were divided into fundamental parts, which “act like electrical atoms”.
In 1894, Stoney coined the term electron to denote this elementary charge. The word electron, a combination of electromagnetism with the ending on, is now used to refer to subatomic particles such as protons and neutrons.
Electron Inventor and Developer
The discoverer of the electron is known to many as Joseph John Thomson , also known as JJ Thomson . But based on some historical records, JJ Thomson continued William Crookes’ experiments . After being developed by JJ Thomson , the discovery of electrons continues to be developed. If sorted, there are several inventors who played a role in the development of electrons, including:
Johann William Hittorf and Eugen Goldstein
The initial discovery of the electron started while a German physicist was working on it. discovered in 1869 in the form of a glow from the cathode. Light emission will increase as the gas pressure decreases. Physicist named Johann William Hittorf , he was born on March 27, 1824 in Bonn, Germany. He died on November 28, 1914. The German physicist Eugen Goldstein showed that these rays cast their shadows, and he named them cathode rays.
William Crookes
William Crookes was born in England in 1832 in England. He is a physicist and chemist. After the advent of cathode rays, in 1870, William Crookes conducted experiments to build the first vacuum cathode ray tube. Through the tube he built, William Crookes demonstrated the appearance of visible light rays from inside the tube and these rays carried energy and traveled from the cathode to the anode.
In fact, he can use the magnetic field used to bend the fingers. Thus, he was able to show that visible light carried a negative charge. Thus, he stated that cathode rays were negatively charged particles that were present in all matter and had mass. Then in 1879, William Crookes named his discovery, radian materials.
JJ Thomson is with John S. Townsend and HA Wilson
JJ Thomson with his experimental friends, John S. Townsend and HA Wilson conducted experiments to develop the cathode ray tube invented by William Crookes . JJ Thomson and two colleagues not only developed the cathode ray tube, but also wanted to show that cathode rays were a new particle.
They then carried out three experimental tests on the effects of magnetic and electric fields in a cathode ray tube. In accordance with the experiments that have been done. JJ Thomson concluded that cathode rays are one of the particles that make up atoms with a negative charge.
After JJ Thomson’s discovery succeeded, an Irish physicist named George F. Fitzgerald named the particle he discovered, the electron. These negatively charged electrons are what we know today, especially in the process of forming atoms or subatomic particles.
So it is often said that the electron was discovered by JJ Thomson . JJ Thomson was born in Cheetham Hill, Manchester, England on December 18, 1856. He died aged 83 on August 30, 1940 in Cambridge, England.
Henri Becquerel
After JJ Thomson conducted experiments and developed cathode rays and electrons, there was a physicist named Henri Becquerel and he came from France. In his experiments, Henri Becquerel said that there are alpha and beta particles. The appearance of these two particles is because they can penetrate physical objects.
Then, in 1900, Henri Becquerel wanted to show that electrons are part of the particles that make up the atom. To prove it, he conducted research and from this research came to the conclusion that the beta rays emitted by radium could be deflected by an electric field. Furthermore, Henri Becquerel concluded that the mass-to-charge ratio is the same as the mass-to-charge ratio of cathode rays.
Robert Andrews Millikan
Robert Andrews Millikan also known as Robert Millikan was born on March 22, 1868 in Morrison. He was a physicist who wanted to measure electrons precisely by conducting an oil drop experiment. The experiment was carried out in 1909 and published in 1911. Robert Millikan ‘s experiment used an electric field.
The electric field in this experiment prevented the falling of the charged oil droplets due to the gravitational force. The instrument used by Robert Millikan can measure charges from 1 to 150 ions with the warning that the error is less than 0.3%. He died on December 19, 1953.
Charles Wilson
In the early 20th century, it was discovered that there is a rapid movement of charged particles and under certain conditions can lead to the emergence of water vapor particles through saturation condensation along the particle stream. With such a principle, in 1911, Charles Wilson created a cloud chamber, in which the cloudy space can catch all paths of electrically charged particles that can move at high speed.
Properties of Electrons
Atoms consist of three constituent particles with very different electrical charges. The negatively charged particles that make up atoms are electrons. These are the properties of electrons!
1. As Elementary Particles
According to the Encyclopedia Britannica, electrons have no visible structure and cannot be reduced or broken down into smaller components. Thus, the electron is an elementary particle, also known as an elementary particle.
2. Negatively Charged
As mentioned earlier, electrons are the negatively charged particles that make up atoms. The charge of the electron is -1 (the reciprocal of the proton).
3. Has a Small Mass
4. Found in Electron Atomic Orbitals
Not found in the atomic nucleus or nucleus. The electrons found in the space around the atomic nucleus are called orbitals. In orbitals, electrons orbit the atomic nucleus at different energies. However, the exact position of the electron in an atom cannot be determined, according to the Heisenberg uncertainty principle.
5. Spin
The next property of electrons is spin or spin. According to Metaphysical Concepts, electrons have an intrinsic angular momentum and a magnetic moment that causes them to spin and is called the spin of the electron.
The angular momentum of the quantum number it has. Meanwhile, electrons only have two possible spin directions, namely in the direction of the magnetic field (up) and away from the magnetic field (down). So the quantum number of an electronic battery can be +1/2 or -1/2. The two orientations of the electron spins lead to the filling of the orbitals.
According to the Khan Institute, only two electrons can fill a given orbital with opposite spins. This consequence is known as the Pauli exclusion principle.
Electron Interaction
Electrons create an electric field that attracts positively charged particles such as protons and repels other negatively charged particles. This force of attraction/repulsion is determined by Coulomb’s law. When the electrons move, they create a magnetic field. The Ampere-Maxwell law relates the magnetic field to the motion of the electron mass (current) relative to an observer. The electromagnetic field of moving charge carriers is represented using Liénard-Wiechert potentials, which hold even for particles moving close to the speed of light.
When electrons move in a magnetic field, Lorentz forces affect the direction of the electron orbitals perpendicular to the magnetic field lines and the speed of the electrons. This centripetal force causes the electron orbits to take a spiral shape.
The acceleration resulting from this curved motion causes the electrons to emit energy in the form of synchrotron radiation. This energetic emission can then bounce off the electrons, known as the Abraham-Lorentz-Dirac force, which creates friction that slows the electrons down. . This force is due to the reverse reaction of the electron field with itself.
In quantum electrodynamics, electromagnetic interactions between particles are mediated by photons. Isolated electrons that are not accelerated cannot emit or absorb photons; if it absorbs or emits a photon, it violates the law of conservation of energy and momentum.
However, virtual photons can transfer momentum between two charged particles. It is this exchange of virtual photons that produces the Coulomb force. Energy emission can occur when moving electrons are deflected by charged particles such as protons. The acceleration of electrons causes the emission of Bremsstrahlung radiation.
The elastic collision between photons (light) and free electrons is called Compton scattering. These collisions generate momentum and energy transfer between the particles, which changes the wavelength of the photon by some Compton shift.
The maximum magnitude of this wavelength shift is h/mec, which is known as the Compton wavelength. For an electron, it is 2.43 × 10−12 m. [60] If the wavelength of light is long (for example, the wavelength of visible light is 0.4-0.7 m) then the shift in wavelength becomes very small. The interaction between light and free electrons is called Thomson scattering.
The relative strength of the electromagnetic interaction between two charge carriers such as electrons and protons is given by the fine structure constant. The value of this constant is dimensionless and is the ratio of two energies: the electrostatic energy of the attraction (or repulsion) at the Compton wavelength separation to the residual energy of the load. This is 7.297353 × 10−3, or approximately 1⁄137.
When an electron and a positron collide, they annihilate each other, producing two or more gamma photon rays. If the electron and positron have negligible momentum, a positronium atom can form before annihilation, producing two or three gamma-ray photons with an energy of 1.022 MeV.
On the other hand, high-energy photons can turn into electrons and positrons back in a process called pair production, but only in the presence of a nearby charged particle, such as the atomic nucleus.
The Role of Electrons in Everyday Life
Here are 5 complete roles of electrons in everyday life.
- Deep electron X-rays X-rays are used to diagnose or analyze disease, usually to examine damaged areas and the lungs.
- Electrons are also used in microscopes to manipulate light and display images, resulting in greater and better resolution.
- Making fireworks also requires electrons to make sparks of beautiful colors.
- Transport oxygen throughout the body.
- Electrons are also used in radiation therapy to cure cancer cells.