Chapter 5 Flashcards
Nuclear physics
What is an Alpha-particle (α)?
Radiation consisting of helium ions with a double positive charge (⁴₂He)
Alpha-particles are emitted during certain types of radioactive decay.
Define an Atom.
Tiny constituent of matter
Atoms are the basic units of chemical elements.
What is Background radiation?
Ever-present radiation resulting from cosmic rays from outer space and radioactive materials in rocks, the air, buildings
This radiation is a natural part of the environment.
What is a Beta-particle (β)?
Radiation consisting of high-speed electrons (_₀⁻₁e)
Beta-particles are produced during beta decay.
What is an Electron?
Negatively charged elementary particle (_₀⁻₁e)
Electrons are fundamental components of atoms.
Define Gamma-radiation (γ).
High-frequency, very penetrating electromagnetic waves
Gamma radiation is often emitted alongside alpha and beta radiation.
What is Half-life?
The average time for half the nuclei in a radioactive sample to decay
Half-life is a key concept in understanding radioactive decay.
Define an Ion.
Charged atom or molecule that has lost or gained one or more electrons so that it is no longer neutral
Ions can be positively charged (cations) or negatively charged (anions).
What is an Isotope?
One form of an element that has the same number of protons but a different number of neutrons in the nucleus from other isotopes of the same element
Isotopes can be stable or radioactive.
What is a Neutron?
An uncharged subatomic particle found in the nucleus of an atom (except that of hydrogen)
Neutrons play a crucial role in the stability of atomic nuclei.
Define Nucleon number, A.
Number of protons and neutrons in the nucleus
This number is used to identify isotopes.
What is a Proton?
Positively charged particle found in the nucleus of an atom
Protons determine the atomic number of an element.
Define Proton number, Z.
Number of protons in the nucleus
The proton number is unique for each element.
What is Fission?
The break-up of a large nucleus into smaller parts
Fission is a process used in nuclear reactors and atomic bombs.
What is Fusion?
The union of light nuclei into a heavier one
Fusion is the process that powers the sun and other stars.
