Radioactivity Flashcards
Define: radiation
the emission of energy either as wave or particle
Define: background radiation
ionising radiation in our environment which can be natural or artificial
Define: ionising radiation
has enough energy to ionise (remove an electron from an atom), which can change the chemical composition of the material
Define: non-ionising radiation
has enough energy to excite molecules and atoms, causing them to vibrate faster
List 3 sources of natural background radiation
Isotopes in rocks, plants and animals, cosmic rays
List 3 sources of artificial background radiation
medical procedures, nuclear power or weapons, industrial sterilisation or gauging devices
Define: isotope
Atoms of the same element with varying amounts of neutrons, leading to different atomic weights.
Define: radioisotope
isotopes emitting radiation to achieve a more stable form
Define: half-life
the amount of time it take for a radioisotope to decay in half
List the types of nuclear decay
alpha (α), beta (β), gamma (γ)
Describe alpha radiation
2 neutrons, 2 protons (equivalent to a helium nuclei)
Describe beta radiation
1 electron
Describe gamma radiation
electromagnetic particle
Describe the penetration depth of alpha radiation
Stopped by paper or a few centimetres of air
Describe the penetration depth of beta radiation
Stopped by a few millimetres of aluminium
