What is the Value of Electrons?
An electron is a subatomic (smaller than an atom) light particle that carries a single unit of negative electricity, represented as - e. Electrons can either be free (meaning not attached to the atom) or bound with the nucleus. The charge of the electron is equal to the magnitude of the elementary charge (e) however, holding a negative sign (-e), the value of the basic unit of charge or elementary charge is 1.6 x 10-19 C. Therefore,
It is one of the important constants of nature.
Electron Charge
The charge on a single electron (e) is regarded as the unit electrical charge. It is designated as a negative polarity. The charge on an electron is equal, however, opposite to the positive charge on a proton or hole.
Mass of Electron
Electrons have a mass of 0 amu (atomic mass unit) when they orbit the nucleus and have a charge of -1.
The invariant mass of the electron is given by,
Which is a very small value.
Here, the invariant mass is the rest mass mass or the mass of a stationary electron.
In atomic mass units (amu), the mass of an electron is given by,
Charge of Electron in eV
The charge of an electron is -1, and its mass is about 1/2000 of the mass of a neutron or proton. The electron charge is usually represented by the symbol e. This is the basic physical constant used to represent 1.1602 × 10-19 coulomb, a unit of naturally occurring charge. Therefore, the charge of the electron is 1.602 x 10-19 C. In the centimeter gram second unit system (CGS), it is 4.80320425 (10) x 10-10 statcoulomb.
In physics, eV stands for electron volt and it is the amount of kinetic energy gained by an electron while accelerating from rest position through an electric potential difference of one volt in vacuum.
Electron volt is the unit of energy generally used in atomic and nuclear physics which is equal to the energy gained by an electron or a charged particle carrying unit electric charge when the electrical potential at the electron increases by 1 Volt.
Where value of 1 erg = 10-7 Joule
So,
Mass of an Electron
The mass of an electron is known to be 1/1836 of the mass of a proton. The electron mass values are:
me = 9.10938356 × 10-31 kg
Electron charge and mass values are often used to solve physical problems.
Mass of an electron in eV or electron volt is this mass corresponding to a rest energy given by,
Value of Charge
The quantization of electric charge is the property by virtue of which all free charges are an integral part of a basic unit of charge represented by e. Therefore, the charge q of a body is given by,
Where n is any integer, positive or negative. The fundamental charge is the charge that an electron or proton carries, by convention, the charge on an electron is negative. Therefore, charge on an electron is written as (e -1) while the charge on proton is (+e).
The value of the basic unit of elementary charge is given by,
This is one of the fundamental constants used in physics.
If a body carries n1 electrons and n2 protons,then total charge on the body will be:
As n1, n2 are integers so their difference must also be an integer. Hence the charge on any body is an integral multiple of e.
The SI unit of charge is coulomb or C.
The CGS (centimeter-gram-second) unit of charge is 1 electrostatic (e.s.u) of charge or stat charge.
Another unit of charge is one electromagnetic unit (e.m.u) of charge, where
Charge of One Electron
Any charged body or charged particle can possess charge equal to +/- e , +/- 2e, +/- 3e, +/- 4e and so on, i.e The possible value of charge for one electron will be given by.
Taking the equation: q = ne (putting n = 1), we get,
Energy Level
Atoms have several energy bands and energy gaps. All electrons are situated in one of the energy bands. Every atom has a valence band and a conduction band. The gap which is present between the two bands, valence band and the conduction band, is what we call the forbidden energy gap. The gap also determines the electrical properties of the material.
Difference Between Charge and Electron
About Electrons
Electrons are small subatomic particles that orbit the nucleus in an energy shell called an orbit. These subatomic particles carry a negative charge of 1.602 × 10-19 coulombs. The electron mass is 9 × 10-31 kg. Electrons orbit the core within the shell, continuously increasing energy. H. Shells closer to the core have less energy than the outermost shells. Electrons which are available in the outermost shell of an atom are called valence electrons. The vertical groups in the periodic table represent the valence electrons of an atom, that is, the number of electrons present in the valence electrons.
Valence Electrons
Simply put, valence electrons are electrons that are constantly rotating in the outermost shell or orbit of an atom. The outermost shell, or valence shell, is the shell with the highest energy. Therefore, the electrons in the valence shell have the highest energy compared to the electrons in the internal orbit. This shell is at a distance away from the core. As a result, they can be attracted to the nucleus of another atom as much as or more than they are in their nucleus.
These electrons exist in the s orbital and the p orbital. The electrons that exist in the inner shell are core electrons. During the formation of chemical bonds, there is a loss, gain, or sharing of valence electrons. Valence electrons play an important role in most chemical reaction because they contain more energy than electrons in internal orbitals. In addition, valence electrons are characteristic of the Chemistry of elements. Valence electrons give us an idea of how easy it is for an atom to form a bond, how many unpaired electrons there are, and how many atoms can participate in a given chemical reaction.
FAQs on Value of Electron
1. What does the term 'quantum of charge' signify when discussing the electron?
The term 'quantum of charge' refers to the smallest independent unit of electric charge that can exist. For the electron, this means its charge is the fundamental unit, denoted as 'e'. All observed electric charges are integer multiples of this elementary charge. This concept highlights that charge is not continuous but exists in discrete packets.
2. What is the fundamental charge of an electron, and why is it considered elementary?
The fundamental charge of an electron is approximately -1.602 x 10-19 Coulombs (C). It is considered elementary because it is the smallest known indivisible unit of charge carried by a free particle. All other charges found in nature are either multiples or specific fractions of this elementary charge, making it a cornerstone in understanding electrical phenomena in physics.
3. What are the essential physical properties of an electron?
Electrons possess several essential physical properties:
- Charge: They carry a fundamental negative electric charge of approximately -1.602 x 10-19 C.
- Mass: They have a very small rest mass, approximately 9.109 x 10-31 kg.
- Spin: Electrons have an intrinsic angular momentum, often referred to as spin (either spin-up or spin-down).
- Wave-Particle Duality: They exhibit characteristics of both waves and particles.
- Point Particle: Current understanding suggests electrons are point-like particles, meaning they have no internal structure or measurable size.
4. What is the typical mass of an electron, and how is it expressed in different units?
The rest mass of an electron is approximately 9.109 x 10-31 kilograms (kg). This value is extremely small. To express it in grams, you would convert kilograms to grams (since 1 kg = 1000 g), resulting in roughly 9.109 x 10-28 grams (g). Sometimes, its mass is also expressed in atomic mass units (amu) for convenience in atomic calculations or in terms of electron-volts (eV/c2) when dealing with energy-mass equivalence.
5. How does the mass of an electron change when it moves at very high speeds, close to the speed of light?
According to Einstein's special theory of relativity, the mass of an electron (or any object) appears to increase as its speed approaches the speed of light. This phenomenon is known as relativistic mass increase. As an electron moves faster, its effective mass becomes greater than its rest mass. If an electron could reach the speed of light, its mass would theoretically become infinite, which is why massive particles cannot attain the speed of light. This effect is particularly noticeable in high-energy physics experiments like those in particle accelerators.
6. How do the fundamental properties of an electron compare with those of a proton?
Electrons and protons are both fundamental subatomic particles, but they have distinct properties:
- Charge: An electron has a negative charge (approximately -1.602 x 10-19 C), while a proton has an equal and opposite positive charge (+1.602 x 10-19 C).
- Mass: A proton is significantly more massive than an electron. A proton's mass (approximately 1.672 x 10-27 kg) is about 1836 times greater than an electron's rest mass.
- Location: In an atom, electrons orbit the nucleus, whereas protons are found within the nucleus.
- Composition: Electrons are considered elementary particles, meaning they are not made of smaller components. Protons, on the other hand, are composed of smaller particles called quarks.
7. Why is understanding the precise values of electron properties crucial in various areas of physics?
Understanding the precise values of electron properties, such as its charge and mass, is crucial because electrons are fundamental to almost all physical and chemical phenomena. These exact values are essential for:
- Accurately calculating forces and energies in electric and magnetic fields.
- Explaining the behavior of electric current and the operation of electronic devices.
- Formulating models of atomic structure and chemical bonding.
- Developing technologies like electron microscopes, X-ray machines, and semiconductors.
- Advancing theories in quantum mechanics and particle physics, where the electron's properties define its role in the fundamental laws of the universe.
8. In what real-world applications or phenomena is the 'value of electron' particularly significant?
The 'value of electron' (referring to its fundamental properties like charge and mass) is incredibly significant across numerous real-world applications and natural phenomena:
- Electricity and Electronics: The controlled flow of electrons is the basis of all electric currents, powering every electronic device from mobile phones to computers.
- Lighting Technology: Fluorescent lamps and LED lights work by exciting electrons, which then release energy as light.
- Medical Imaging: X-ray machines produce images by directing high-energy electrons, while MRI relies on the spin of electrons and atomic nuclei.
- Chemical Reactions: The 'value of electron' dictates how atoms form bonds, influencing the properties of all materials and chemical reactions.
- Particle Accelerators: These powerful machines accelerate electrons to extremely high energies to probe the fundamental structure of matter and energy.
