| A | B |
|---|
| atom | The basic unit of a substance |
| nucleus | The central part of an atom |
| electron | Small light negatively charged particle |
| proton | Positively charged particle that exists in a nucleus with a unit of mass |
| neutron | Neutral particle that exists in a nucleus and contributes to the mass and binding of the nucleus |
| rutherford scattering | The scattering of alpha particles by nuclei of heavy atoms that suggests the existence of a small |
| emission spectra | Charectistics set of wavelenghts of light that come from an atom when it is excited |
| absorption spectra | Chareteristic set of wavelengths that an element will absorb from white light |
| quantisation | Having things with discrete values |
| energy level | An allowed ammount of energy that an atom or a nucleus can have. |
| isotopes | Different types of atoms containing the same numbers of protons but different numbers of neutrons |
| nuclide | A type of atom with a specific nuclear composition |
| mass number | Number of nucleons in the nucleus of atom |
| atomic number | Number of protons in the nucleus of an atom |
| strong nuclear force | Attractive short range force that holds nucleons together in a nucleus |
| ionising | Breaking up into charged particles |
| alpha | Emission from unstable nulceus consisting high energy helium nucleus |
| beta | Emission from an unstable nucleus consisting high energy electron |
| gamma | Emission from an unstable nucleus consisting high energy electromagnetic wave |
| penetration | Ability to pass through objects without being absorbed |
| nuclear equation | Balanced description of changes to nucliides in a nuclear reaction |
| half life | Time taken for number of unstable nucleons to halve (time for activity to halve) |
| mass defect | Difference between mass of nucliide and masses of component parts arising from binding |
| binding energy | Energy released when a nucliide is formed from its constituent particles |
| fission | Splitting of large nucliides that results in the release of energy |
| fusion | Joining of small nucliides that results in the release of energy |
