give at least three proofs to show that electrons are present in all atoms.
Answers
Answer:Thomson's experiments with cathode ray tubes showed that all atoms contain tiny negatively charged subatomic particles or electrons. Thomson's plum pudding model of the atom had negatively-charged electrons embedded within a positively-charged "soup."
Explanation:
Explanation:
The electron is a subatomic particle, symbol
e−
or
β−
, whose electric charge is negative one elementary charge.[9] Electrons belong to the first generation of the lepton particle family,[10] and are generally thought to be elementary particles because they have no known components or substructure.[1] The electron has a mass that is approximately 1/1836 that of the proton.[11] Quantum mechanical properties of the electron include an intrinsic angular momentum (spin) of a half-integer value, expressed in units of the reduced Planck constant, ħ. Being fermions, no two electrons can occupy the same quantum state, in accordance with the Pauli exclusion principle.[10] Like all elementary particles, electrons exhibit properties of both particles and waves: they can collide with other particles and can be diffracted like light. The wave properties of electrons are easier to observe with experiments than those of other particles like neutrons and protons because electrons have a lower mass and hence a longer de Broglie wavelength for a given energy.
Electron
Hydrogen atomic orbitals at different energy levels. The more opaque areas are where one is most likely to find an electron at any given time.
CompositionElementary particle[1]StatisticsFermionicGenerationFirstInteractionsGravity, electromagnetic, weakSymbol
e−
,
β−
AntiparticlePositron (also called antielectron)TheorizedRichard Laming (1838–1851),[2]
G. Johnstone Stoney (1874) and others.[3][4]DiscoveredJ. J. Thomson (1897)[5]Mass9.1093837015(28)×10−31 kg[6]
5.48579909070(16)×10−4 u[7]
[1822.8884845(14)]−1 u[a]
0.51099895000(15) MeV/c2[6]Mean lifetimestable ( > 6.6×1028 yr[8])Electric charge−1 e[b]
−1.602176634×10−19 C[6]
−4.80320451(10)×10−10 esuMagnetic moment−1.00115965218091(26) μB[7]Spin1/2Weak isospinLH: −1/2, RH: 0Weak hyperchargeLH: -1, RH: −2
Electrons play an essential role in numerous physical phenomena, such as electricity, magnetism, chemistry and thermal conductivity, and they also participate in gravitational, electromagnetic and weak interactions.[12] Since an electron has charge, it has a surrounding electric field, and if that electron is moving relative to an observer, said observer will observe it to generate a magnetic field. Electromagnetic fields produced from other sources will affect the motion of an electron according to the Lorentz force law. Electrons radiate or absorb energy in the form of photons when they are accelerated. Laboratory instruments are capable of trapping individual electrons as well as electron plasma by the use of electromagnetic fields. Special telescopes can detect electron plasma in outer space. Electrons are involved in many applications such as electronics, welding, cathode ray tubes, electron microscopes, radiation therapy, lasers, gaseous ionization detectors and particle accelerators.
Interactions involving electrons with other subatomic particles are of interest in fields such as chemistry and nuclear physics. The Coulomb force interaction between the positive protons within atomic nuclei and the negative electrons without, allows the composition of the two known as atoms. Ionization or differences in the proportions of negative electrons versus positive nuclei changes the binding energy of an atomic system. The exchange or sharing of the electrons between two or more atoms is the main cause of chemical bonding.[13] In 1838, British natural philosopher Richard Laming first hypothesized the concept of an indivisible quantity en an electron collides with a positron, both particles can be annihilated, producing gamma ray photons.