Mass Defect & Binding Energy Experiments into nuclear structure have found that the total mass of a nucleus is less than the sum of the masses of its constituent nucleons This difference in mas...
Representing Simple Nuclear Reactions Nuclear reactions can be represented by balanced equations of nuclei in the AZX form AZX notation for atomic nuclei The top number A represents the nucleon num...
Energy & Mass Equivalence Einstein showed in his theory of relativity that matter can be considered a form of energy and hence, he proposed: Mass can be converted into energy Energy can be conv...
Calculating Discrete Energies The difference between two energy levels is equal to a specific photon energy The energy (hf) of the photon is given by: ΔE = hf = E2 - E1 Where, E1 = Energy of the hi...
Line Spectra Line spectra is a phenomenon which occurs when excited atoms emit light of certain wavelengths which correspond to different colours The emitted light can be observed as a series of co...
Atomic Energy Levels Electrons in an atom can have only certain specific energies These energies are called electron energy levels They can be represented as a series of stacked horizontal lines in...
The de Broglie Wavelength De Broglie proposed that electrons travel through space as a wave This would explain why they can exhibit behaviour such as diffraction He therefore suggested that electro...
Wave-Particle Duality Light waves can behave like particles, i.e. photons, and waves This phenomenon is called the wave-particle nature of light or wave-particle duality Light interacts with matter...
Photoelectric Emission The work function Φ, or threshold energy, of a material is defined as: The minimum energy required to release a photoelectron from the surface of a material Consider the elec...
Threshold Frequency & Wavelength The concept of a threshold frequency is required in order to explain why a low frequency source, such as a filament lamp, was unable to liberate any electrons i...
The Photoelectric Effect: Basics The photoelectric effect is the phenomena in which electrons are emitted from the surface of a metal upon the absorption of electromagnetic radiation Electrons remo...
The Electronvolt The electronvolt is a unit which is commonly used to express very small energies This is because quantum energies tend to be much smaller than 1 Joule The electronvolt is derived f...
