Nuclear

• Isotopes generally sit above the N-Z line, indicating they have more neutrons than protons
• The further Isotopes are from this curve, the more unstable they are and the more likely they are to decay
• Lighter Isotopes are generally beta minus emitters, while heavier Isotopes are alpha emitters
• Beta plus emitters do not exist naturally as they require proton doping to produce the right Isotope, placing them under the curve
• Unstable Isotopes move through a Decay chain to end up at a stable Isotope
• An alpha or beta decay can leave the nucleus at an excited energy state, emitting a gamma Photon
• Some Isotopes can remain in a metastable state after Decay, emitting gamma radiation at a later time
• The relative mass of nuclei is based on the relative atomic mass unit U, defined as 1/12th the mass of a carbon 12 atom
• A helium nucleus, if split into its constituent nucleons, will have a mass of more than 4 U due to the work required to overcome the strong nuclear force
• Average binding energy per nucleon follows a specific pattern on a graph against mass number
• One U of mass converted into energy gives 931.5 Mega electron volts
• Binding energy is the energy needed to separate a nucleus, with Iron 56 being the most stable Isotope
• Fusion and fision involve nuclei turning into other more stable nuclei, releasing energy in the process
• Nuclear waste must be disposed of safely, often by cooling in ponds and vitrifying in glass for deep underground storage
• Activity is given by the equation A = Lambda * N, where Lambda is the Decay constant and N is the number of undecayed nuclei
• The activity at a given time compared to initial activity can be calculated using the exponential decay equation
• Intensity of gamma radiation is inversely proportional to distance squared
• Electron defraction can be used to measure the diameter of a nucleus
• Ernest Rutherford discovered the positive and small nature of the nucleus relative to the atom size
• Plotting a graph of the log of the radius against the log of mass number results in a straight line with a gradient of 1/3
• Comparing two nuclei to find an unknown radius or nucleon number can be done using the proportionality of R to A^3