Investigating Half-Life Aim of the Experiment The aim of the experiment is to investigate the half-life of a decaying radioactive sample This can be done with a live sample if safe access is availa...
Half-Life It is impossible to know when a particular unstable nucleus will decay But the rate at which the activity of a sample decreases can be known This is known as the half-life Half-life is de...
Decay Equations Changes in N and Z by Radioactive Decay There are four reasons why a nucleus might become unstable, and these determine which decay mode will occur Too many neutrons Decays through ...
Alpha, Beta & Gamma Particles Some elements have nuclei that are unstable This tends to be when the number of nucleons does not balance In order to become more stable, they emit particles and/o...
Background Radiation It is important to remember that radiation is a natural phenomenon Radioactive elements have always existed on Earth and in outer space However, human activity has added to the...
Isotopes AZX Notation A nuclide is a group of atoms containing the same number of protons and neutrons For example, 5 atoms of oxygen are all the same nuclide but are 5 separate atoms Atomic symbol...
Emission & Absorption Spectrum Line Spectra Line spectra is a phenomenon that occurs when excited atoms emit light of certain wavelengths which correspond to different colours This comes from d...
Transitions Between Energy Levels Difference in discrete energy levels The difference between two energy levels is equal to a specific photon energy The energy (hf) of the photon is given by: ΔE = ...
Discrete Energy Levels The Photon Model Photons are fundamental particles that make up all forms of electromagnetic radiation A photon is a massless “packet” or a “quantum” of electromagnetic energ...
