These can happen by fission where a nucleus splits into two parts on absorbing a neutron, or by radioactive decay.
There are many ways a nuclear accident may occur, however most nuclear power plant accident occur due to problem in an reactor.
Nuclear energy
Changes that occur when the composition remains the same
Transitions between various stages of electron excitement.
The dangerous condition that can occur in a nuclear reactor and due to overheating is a nuclear meltdown.
In nuclear reactions the atom itself changes while molecules and/or structural organisation of atoms do in chemical and physical changes.
There are many ways a nuclear accident may occur, however most nuclear power plant accident occur due to problem in an reactor.
Nuclear energy
Radium-226--------------------Radon-222 + alpha
Yes, that is where we get the nuclear material for our reactors, by mining it from the Earth. Though it does not occur in high concentrations, we have to concentrate it ourselves.
Lithium forms in the stars when the light nuclei are forced together and mix with yield energy. Because the mass of the combination will be less than the sum of the masses of the individual nuclei this will result to nuclear fusion.
Because the conditions of temperature and pressure that occur in stars do not occur on earth
Return loss refers to the reflections that occur at changes in impedance.
Physical changes
That lead us into the nuclear/space age. The change was not so radical as changes occur day to day.
changes the occur in relationship
There is not a specific time when weather changes occur except for the changing of the seasons.