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Secondly, he found the charge-to-mass ratio of alpha particles to be half that of the hydrogen ion. Rutherford proposed three explanations: 1) an alpha particle is a hydrogen molecule (H 2 ) with a charge of 1 e ; 2) an alpha particle is an atom of helium with a charge of 2 e ; 3) an alpha particle is half a helium atom with a charge of 1 e .
The two free electrons then travel towards the anode and gain sufficient energy from the electric field to cause impact ionization when the next collisions occur; and so on. This is effectively a chain reaction of electron generation, and is dependent on the free electrons gaining sufficient energy between collisions to sustain the avalanche.
Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus) and thereby transforms or "decays" into a different atomic nucleus, with a mass number that is reduced by four and an atomic number that is reduced by two.
In alpha decay, a particle containing two protons and two neutrons, equivalent to a He nucleus, breaks out of the parent nucleus. The process represents a competition between the electromagnetic repulsion between the protons in the nucleus and attractive nuclear force, a residual of the strong interaction. The alpha particle is an especially ...
In this mode of decay, two of the orbital electrons are captured via the weak interaction by two protons in the nucleus, forming two neutrons (Two neutrinos are emitted in the process). Since the protons are changed to neutrons, the number of neutrons increases by two, while the number of protons Z decreases by two, and the atomic mass number A ...
For example, a neutral chlorine atom has 17 protons and 17 electrons, whereas a Cl − anion has 17 protons and 18 electrons for a total charge of −1. All atoms of a given element are not necessarily identical, however. The number of neutrons may vary to form different isotopes, and energy levels may differ, resulting in different nuclear ...
Here, a proton, consisting of two up quarks and a down, decays into a pion, consisting of an up and anti-up, and a positron, via an X boson with electric charge − 4 / 3 e. In particle physics, proton decay is a hypothetical form of particle decay in which the proton decays into lighter subatomic particles, such as a neutral pion and a ...
If there are more electrons than protons in a piece of matter, it will have a negative charge, if there are fewer it will have a positive charge, and if there are equal numbers it will be neutral. Charge is quantized : it comes in integer multiples of individual small units called the elementary charge , e , about 1.602 × 10 −19 C , [ 1 ...