IntroductionOther basic Atomic ParticlesBeta corpuscle

A common atom consists of 3 subatomic particles: protons, neutrons, and electrons (as checked out in the helium atom below). Various other particles exist as well, such as alpha and beta corpuscle (which are questioned below). The Bohr design shows the three simple subatomic corpuscle in a simple manner. Many of one atom"s massive is in the nucleus—a small, thick area in ~ the facility of every atom, composed of nucleons. Nucleons incorporate protons and also neutrons. Every the hopeful charge of an atom is had in the nucleus, and originates from the protons. Neutrons are neutrally-charged. Electrons, which are negatively-charged, are located outside of the nucleus.

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The Bohr design is outdated, however it depicts the three basic subatomic particles in a comprehensible way. Electron clouds are much more accurate depictions of where electrons space found. Darker locations represent whereby the electron are much more likely to it is in found, and also lighter locations represent where they are much less likely to be found.


ParticleElectric fee (C)Atomic ChargeMass (g)Atomic massive (Au)Spin
Protons +1.6022 x 10-19 +1 1.6726 x 10-24 1.0073 1/2
Neutrons 0 0 1.6740 x 10-24 1.0078 1/2
Electrons -1.6022 x 10-19 -1 9.1094 x 10-28 0.00054858 1/2
Au is the SI symbol for atomic massive unit. The confident charge of protons cancels the an unfavorable charge of the electrons. Neutrons have actually no charge. With regard to mass, protons and also neutrons are really similar, and have a much greater mass than electrons. Compared with neutrons and protons, the mass of one electron is usually negligible. spin is linked with the rotation of a particle. Protons, neutrons, and also electrons each have a total spin that 1/2.


Both the the complying with are ideal ways of representing the ingredient of a details atom:


Often the proton number is not indicated because the elemental symbol conveys the very same information.

Consider a neutral atom that carbon: (ce^12_6C). The atomic mass variety of Carbon is 12 amu, the proton number is 6, and also it has actually no charge. In neutral atoms, the charge is omitted.


Above is the atom symbol for helium indigenous the routine table, v the atomic number, elemental symbol, and mass indicated.

Every facet has a specific variety of protons, for this reason the proton number is not constantly written (as in the second technique above).

# neutrons = atomic Mass Number - Proton Number atom mass number is abbreviated as A. Proton number(or atom number) is abbreviation Z. # proton = Proton Number or atomic Number In neutral atoms, # electron = # Protons In ions, # electrons = # proton - (Charge) Charge is written v the number prior to the optimistic or negative sign Example, 1+

Note: The atomic mass number is no the same as the atom mass seen on the regular table. Click here for much more information.

Other an easy Atomic Particles

Many of this particles (explained in detail below) room emitted through radioactive decay. Click here for more information. Additionally note that countless forms that radioactive degeneration emit gamma rays, which space not particles.

See more: Can You Cube Root A Negative Number, Can You Find The Cube Root Of A Negative Number

Alpha Particles

Alpha particles deserve to be denoted through He2+,α2+, or simply α. They space helium nuclei, i beg your pardon consist of two protons and two neutrons. The network spin on an alpha fragment is zero. They an outcome from large, stormy atoms through a process called alpha decay. Alpha degeneration is the procedure by i m sorry an atom emits one alpha particle, thereby becoming a brand-new element. This just occurs in aspects with large, radiation nuclei. The smallest provided element the emits alpha particles is facet 52, tellurium. Alpha particles are typically not harmful. They can be conveniently stopped by a single sheet of record or by one"s skin. However, castle can reason considerable damage to the insides of one"s body. Alpha decay is offered as a safe power source for radioisotope generators provided in synthetic heart pacemakers and room probes.

Beta+(β+) or Positron Emission

Position emissions occurs when an excess of protons renders the atom unstable. In this process, a proton is converted into a neutron, a positron, and also a neutrino. If the neutron remains in the nucleus, the positron and also the neutrino space emitted. The positron deserve to be called a beta fragment in this instance. The equation because that this process is offered below:

< _1^1 extrmp^+ ightarrow _1^0 extrmn + extrme^+ + u_e >

n = ghost p+ = Proton e+ = Positron (beta particle) νe = Neutrino

β+ Decay