Differing quantities of protons, neutrons, and electrons cause the atom to have differing chemical properties, which determine what element that atom is.Ītoms are unimaginably small, and their nuclei are 1000 times smaller. Surrounding the nucleus is a cloud of much smaller and lighter electrons, which are attracted to the nucleus by the electromagnetic force from interacting with the protons. Protons and neutrons are held together in the nucleus by what's called the strong nuclear force (which is the strongest known force in the universe). It is composed of protons and neutrons (collectively called nucleons) and is responsible for the large majority of the atomic mass. The nucleus is the central, highly dense component of an atom (see figure 2). Notice how much more area the electron cloud occupies compared to the nucleus (although this is still not quite to scale, it is close). A drawing depicting what an atom looks like. The tremendous energy of the sun which is obtained by nuclear fusion, releases trillions of neutrino every second.Figure 2. Neutrino has no charge but travels at a very high speed, similar to the speed of light, and can pass through any solid object. Neutrino: They are similar to electrons formed from nuclear reactions.John Ellis and his fellow workers discovered them in 1979. Gluons: Also found within protons and electrons, they act as exchange particles that help transfer strong force between quarks.A proton contains three quarks (two up quarks and one down quark), whereas a neutron contains (two down quarks and one up quark). Quarks are of six different types: up, down, top, bottom, charm, and strange. However, their exact position in an atom cannot be measured with accuracy. They were independently discovered by Murray Gell-Mann and George Zweig in 1964. Quarks: They are fundamental subatomic particles that makeup protons and electrons.Given below is a table showing the charge, mass, and location of the three sub-atomic particles: Name of the Particle Neutrons are neutral particles with no charge but have a substantial size and mass similar to a proton. They were discovered by James Chadwick in the year 1932 and are denoted by the symbol n or n 0. Neutrons, similar to protons, are made of quarks and gluons. They are also found within the nucleus along with the protons in a tightly packed manner. Protons consist of even smaller particles called quarks and gluons.įound tightly packed with the nucleus, they make up virtually all of the mass of an atom along with the neutrons. They were discovered by Ernest Rutherford in the year 1917 and are denoted by the symbol p or p +. Protons are positively charged particles found within a dense region at the center of the atom called the nucleus. When the number of negatively charged electrons is equal to the number of positively charged protons, the atom is neutral in charge. Thomson discovered it in the year 1897.Įlectrons move so fast around the nucleus that their exact location within an atom cannot be determined with accuracy. The standard symbol used for an electron is e or e –. Unlike protons and neutrons, electrons are fundamental particles much smaller (almost 1800 times) in size than protons and neutrons. They are negatively charged particles that revolve around the nucleus in a fixed orbit. In contrast, electrons are found outside the nucleus in a region called the electron cloud or electron shell.

Electrons and protons are found at the center of the atom within a dense region called the nucleus.

All atoms except hydrogen contain three basic subatomic particles: 1) electrons, 2) protons, and neutrons.

Parts of an atom