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What comprises each atomic particles?

- Atoms are made up of protons, neutrons, and electrons. The protons and neutrons are found together in

the core of the atom, called the nucleus, which is in the center. The electrons are found moving around the

nucleus (at different energy levels) in what is called the electron cloud.

Note that in hydrogen, most all of it is made up of just a lone proton and an electron. There are no neutrons

in the most common isotope of hydrogen (1H).

Protons and neutrons, which are called nucleons when they're found in an atomic nucleus, are further made

of still smaller subatomic particles called quarks.

Identify small particles of sub-atomic particles.

- In physics or chemistry, subatomic particles are the particles, which are smaller than an atom.[1] There

are two types of subatomic particles: elementary particles, which are not made of other particles, and

composite particles.[2] Particle physics and nuclear physicsstudy these particles and how they interact.[3]

The elementary particles of the Standard Model include:[4]

Six "flavors" of quarks: up, down, bottom, top, strange, and charm

Six types of leptons: electron, electron neutrino, muon, muon neutrino, tau, tau neutrino

Thirteen gauge bosons (force carriers): the graviton of gravity, the photon of electromagnetism, the three W

and Z bosons of theweak force, and the eight gluons of the strong force.Composite subatomic particles (such as protons or atomic nuclei) are bound states of two or more

elementary particles. For example, a proton is made of two up quarks and one down quark, while the

atomic nucleus of helium-4 is composed of two protons and twoneutrons. Composite particles include all

hadrons, a group composed of baryons (e.g., protons and neutrons) and mesons (e.g., pionsand kaons).

4 major forces of nature

- 1. Gravity - This force acts between all mass in the universe and it has infinite range.

2. Electromagnetic - This acts between electrically charged particles. Electricity, magnetism, andlight are

all produced by this force and it also has infinite range.

3. The Strong Force - This force binds neutrons and protons together in the cores of atoms and is a short

range force.

4. Weak Force - This causes Beta decay (the conversion of a neutron to a proton, an electron and an

antineutrino) and various particles (the "strange" ones) are formed by strong interactions but decay viaweak interactions (that's what's strange about "strangeness"). Like the strong force, the weak force is also

short range.

The weak and electromagnetic interactions have been unified under electroweak theory (Glashow,

Weinberg, and Salaam were awarded the Nobel Prize for this in 1979). Grand unification theories attempt

to treat both strong and electroweak interactions under the same mathematical structure; attempts to include

gravitation in this picture have not yet been successful.

Who discovered and when

Neutrons

The British experimental physicist James Chadwick discovered the neutron in 1932. Of the three

fundamental particles that make up atoms, the electron, the proton and the neutron, the neutron was the last

to be discovered. It's lack of a charge made it more elusive than its companions. Links can be found below.

The existence of a "neutral element" within the atom was suggested by Ernest Rutherford in 1920 and was

proposed by Santiago Antunez de Mayolo at the Third Scientific Pan-American Congress in 1924.