explain the particle model of light in terms of photons with particular energy and frequency.

• describe the impact of de Broglie’s proposal that any kind of particle has both wave and particle properties

• gather, process, analyse and present information and use available evidence to assess the contributions made by Heisenberg and Pauli to the development of atomic theory

• discuss Pauli’s suggestion of the existence of the neutrino and relate it to the need to account for the energy distribution of electrons emitted in beta decay

• account for the need for the strong nuclear force and describe its properties

• describe how neutron scattering is used a s a probe by referring to the properties of neutrons

• identify the ways by which physicists continue to develop their understanding of matter, using accelerators as a probe to investigate the structure of matter

• discuss the key features and components of the standard model of matter, including quarks and leptons.

• describe how the positron emission tomography (PET) technique is used for diagnosis

• identify data sources, gather and process information to compare the advantages and disadvantages of X-rays, CAT scans, PET scans and MRI scans.

• describe the technology needed to measure astronomical spectra

• describe how spectra can provide information on surface temperature, rotational and translational velocity, density and chemical composition of stars.

• use available evidence to assess the impact of technology, including the development of the microscope on the development of the cell theory

• discuss the significance of technological advances to developments in the cell theory.

• distinguish between stable and radioactive isotopes and describe the conditions under which a nucleus is unstable

• use available evidence to analyse benefits and problems associated with the use of radioactive isotopes in identified industries and medicine.

describe the use of atomic absorption spectroscopy (AAS) in detecting concentrations of metal ions in solutions and assess its impact on scientific understanding of the effects of trace elements.

• outline the process of radioactive decay of atomic nuclei

• explain how the relative percentage of remnant radio-isotopes can be used to measure absolute ages of materials, including rocks.

outline stable isotope evidence for the first presence of life in 3.8 x 10⁹ year-old rocks.