P6 - Radioactivity
P6c - electrons and orbits
P6d - background radiation
P6a - atomic models
P6b - inside atoms
plum pudding model - the atom was arranged as a positive charge (proton) throughout with electrons scattered inside.
P6e - types of radiation
P6f - radioactive decay
P6h - dangers of radioactivity
P6g - half life
alpha particle scattering experiment - proved the plum pudding model inaccurate. The alpha particles were supposed to rebound off the foil but instead went straight through.
rutherford's model
isotope - each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties.
ion - has no overall charge
background radiation - ionising radiation that is around us constantly, some is naturally occuring while some originates from human activities
ionising radiation - radiation that can cause ions (charged particles) to form. can cause genetic mutations and tissue damage.
49% radon gas, 15% medical, 13% ground & buildings, 12% cosmic rays, 10% food & drink, 1% nuclear & other.
beta radiation - medium penetration, medium ionising
how to measure radiation: 1) geiger-muller tube 2) photographic film
gamma radiation - good penetration, only slightly ionising
alpha radiation - poor penetration, highly ionising
5 types of radiation: alpha, beta, gamma, positron, neutron.
becquerel is a measurement for radioactive decay - one decay per second
the more unstable particles there are, the more likely it'll decay
half life is the amount of time it takes for half of the unstable nuclei to decay