MCAT Physics

Nuclear Physics

MCAT Physics > Nuclear Physics


Atomic Number is the number of protons in the nucleus (nucleons).

All atoms of an element have the same atomic number and no elements have the same atomic number.

Atomic Mass is the number of protons and neutrons in the nucleus

Isotopes are atoms of the same element with varying amounts of neutrons and thus have different mass numbers

Atomic Weight is the average mass of one mole of a given element (g/mol). It accounts for isotopes and is weighted according to the natural abundances of the various isotopes

Avogadro's number 1 mole = 6.0 x 1023 particles

Mass Defect is the phenomenon that states that there is a difference between the mass of unbound constituents and the mass of the formed nucleus. The unbound constituents have more energy and therefore more mass than the bound constituents. It is the amount of mass converted to energy (heat, light, EM radiation) through the nuclear reactions

E = mc2

Nuclear Binding Energy is the amount of energy that is released when the nucleons (protons and neutrons) bind together through the strong nuclear force, which overcomes the electrostatic repulsion of protons over very short distances. The more binding energy per nucleon released, the more stable the nucleus, which peaks at iron (Fe)

Nuclear Reactions

Nuclear Reactions involve the splitting or combining of atoms. Due to the binding energy per nucleon being greatest (most stable) for intermediate atoms, when small or large atoms combine, a large amount of energy is released

Nuclear Fusion

MCAT Nuclear Physics - Nuclear Fusion

Nuclear Fusion occurs when small nuclei combine into larger ones. This process naturally occurs inside the sun and is responsible for the generation of a massive amount of energy (4 x 1026 J/s)

Nuclear Fission

MCAT Nuclear Physics - Nuclear Fission

Nuclear Fission is a non-spontaneous process in which a large nucleus splits into smaller nuclei and is usually induced by various means. It causes a chain reaction as the neutrons are ejected and releases a large amount of energy when split

Radioactive Decay

See Radioactive Decay

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