Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 4.48C - Know that condensation polymerisation, in which a dicarboxylic acid reacts with a diol, produces a polyester and water. Specification Point 4.49C - Understand how to write the structural and displayed formula of a polyester, showing the repeat unit, given the formulae of the monomers from which it is formed including the reaction of ethanedioic acid and ethanediol. Specification Point 4.50C - Know that some polyesters, known as biopolyesters, are biodegradable. Complete set of Chapter 7 Lessons are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 4.44 - Know that an addition polymer is formed by joining up many small molecules called monomers. Specification Point 4.45 - Understand how to draw the repeat unit of an addition polymer, including polyethene, polypropene, polychloroethene and polytetrafluoroethene. Specification Point 4.46 - Understand how to deduce the structure of a monomer from the repeat unit of an addition polymer and vice versa. Specification Point 4.47 - Explain problems in the disposal of addition polymers. Complete set of Chapter 7 Lessons are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 1.5C - Know what is meant by the term solubility in the units grams per 100 grams of solvent. Specification Point 1.6C - Understand how to plot and interpret solubility curves. Specification Point 1.7C - Practical: investigate the solubility of a solid in water at a specific temperature. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.1.2 - Memory. Factors affecting the accuracy of eyewitness testimony: misleading information, including leading questions and post-event discussion; anxiety. Improving the accuracy of eyewitness testimony, including the use of the cognitive interview. Complete set of Chapter 2 Lectures are available.

Companion PDF worksheet for Edexcel IGCSE Physics Lecture 30 - Fission and Fusion. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 7.17 - Know that nuclear reactions, including fission, fusion and radioactive decay, can be a source of energy. Specification Point 7.18 - Understand how a nucleus of U-235 can be split by collision with a neutron, and that this process releases energy as kinetic energy of the fission products. Specification Point 7.19 -Know that the fission of U-235 produces two radioactive daughter nuclei and a small number of neutrons. Specification Point 7.20 - Describe how a chain reaction can be set up if the neutrons produced by one fission strike other U-235 nuclei. Specification Point 7.21 - Describe the role played by the control rods and moderator in the fission process. Specification Point 7.22 - Understand the role of shielding around a nuclear reactor. Specification Point 7.23 - Explain the difference between nuclear fusion and nuclear fission. Specification Point 7.24 - Describe nuclear fusion as the creation of larger nuclei resulting in a loss of mass from smaller nuclei, accompanied by a release of energy. Specification Point 7.25 - Know that fusion is the energy source for stars. Specification Point 7.26 - Explain why nuclear fusion does not happen at low temperatures and pressures, due to electrostatic repulsion of protons. Complete set of Chapter 7 Worksheets are available.

Companion PDF worksheet for Edexcel IGCSE Physics Lecture 31 - The Universe. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 8.2 - Know that the universe is a large collection of billions of galaxies, that a galaxy is a large collection of billions of stars and that our solar system is in the Milky Way galaxy. Specification Point 8.3 - Understand why gravitational field strength, g, varies and know that it is different on other planets and the Moon from that on the Earth. Specification Point 8.4 - Explain that gravitational force causes moons to orbit planets, causes the planets to orbit the Sun, causes artificial satellites to orbit the Earth and causes comets to orbit the Sun. Specification Point 8.5 - Describe the differences in the orbits of comets, moons and planets. Specification Point 8.6 - Use the relationship between orbital speed, orbital radius and time period. Complete set of Chapter 8 Worksheets are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 7.17 - Know that nuclear reactions, including fission, fusion and radioactive decay, can be a source of energy. Specification Point 7.18 - Understand how a nucleus of U-235 can be split by collision with a neutron, and that this process releases energy as kinetic energy of the fission products. Specification Point 7.19 -Know that the fission of U-235 produces two radioactive daughter nuclei and a small number of neutrons. Specification Point 7.20 - Describe how a chain reaction can be set up if the neutrons produced by one fission strike other U-235 nuclei. Specification Point 7.21 - Describe the role played by the control rods and moderator in the fission process. Specification Point 7.22 - Understand the role of shielding around a nuclear reactor. Specification Point 7.23 - Explain the difference between nuclear fusion and nuclear fission. Specification Point 7.24 - Describe nuclear fusion as the creation of larger nuclei resulting in a loss of mass from smaller nuclei, accompanied by a release of energy. Specification Point 7.25 - Know that fusion is the energy source for stars. Specification Point 7.26 - Explain why nuclear fusion does not happen at low temperatures and pressures, due to electrostatic repulsion of protons. Complete set of Chapter 7 Lessons are available.

PowerPoint lecture covering the following in a modern, concise format: Specification Point 4.1.1.1 - Energy stores and systems. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 8.2 - Know that the universe is a large collection of billions of galaxies, that a galaxy is a large collection of billions of stars and that our solar system is in the Milky Way galaxy. Specification Point 8.3 - Understand why gravitational field strength, g, varies and know that it is different on other planets and the Moon from that on the Earth. Specification Point 8.4 - Explain that gravitational force causes moons to orbit planets, causes the planets to orbit the Sun, causes artificial satellites to orbit the Earth and causes comets to orbit the Sun. Specification Point 8.5 - Describe the differences in the orbits of comets, moons and planets. Specification Point 8.6 - Use the relationship between orbital speed, orbital radius and time period. Complete set of Chapter 8 Lessons are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.8.2.2 - Regulation of transcription and translation. Complete set of Chapter 8 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 8.2 - Know that the universe is a large collection of billions of galaxies, that a galaxy is a large collection of billions of stars and that our solar system is in the Milky Way galaxy. Specification Point 8.3 - Understand why gravitational field strength, g, varies and know that it is different on other planets and the Moon from that on the Earth. Specification Point 8.4 - Explain that gravitational force causes moons to orbit planets, causes the planets to orbit the Sun, causes artificial satellites to orbit the Earth and causes comets to orbit the Sun. Specification Point 8.5 - Describe the differences in the orbits of comets, moons and planets. Specification Point 8.6 - Use the relationship between orbital speed, orbital radius and time period. Complete set of Chapter 8 Lectures are available.

Companion PDF worksheet for Edexcel IGCSE Physics Lecture 25 - Magnetism. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 6.1 - Use the following units: ampere (A), volt (V) and watt (W). Specification Point 6.2 - Know that magnets repel and attract other magnets and attract magnetic substances. Specification Point 6.3 - Describe the properties of magnetically hard and soft materials. Specification Point 6.4 - Understand the term magnetic field line. Specification Point 6.5 - Know that magnetism is induced in some materials when they are placed in a magnetic field. Specification Point 6.6 - Practical: investigate the magnetic field pattern for a permanent bar magnet and between two bar magnets. Specification Point 6.7 - Describe how to use two permanent magnets to produce a uniform magnetic field pattern. Complete set of Chapter 6 Worksheets are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.1.1 - Social influence. Types of conformity: internalisation, identification and compliance. Explanations for conformity: informational social influence and normative social influence. Variables affecting conformity including group size, unanimity and task difficulty as investigated by Asch. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.3.4.1 - Mass transport in animals. Complete set of Chapter 3 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.7.4 - Populations in ecosystems. Complete set of Chapter 7 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 1.22 - Practical: investigate how extension varies with applied force for helical springs, metal wires and rubber bands. Specification Point 1.23 - Know that the initial linear region of a force-extension graph is associated with Hooke’s law. Specification Point 1.24 - Describe elastic behaviour as the ability of a material to recover its original shape after the forces causing deformation have been removed. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 9.1 - Understand the different ways of defining development, using economic criteria and broader social and political measures. Complete set of Chapter 10 Lectures are available.

Companion PDF worksheet for Edexcel IGCSE Biology Lecture 37 - Reproduction in Plants. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 3.3 - Describe the structures of an insect-pollinated and a wind-pollinated flower and explain how each is adapted for pollination. Specification Point 3.4 - Understand that the growth of the pollen tube followed by fertilisation leads to seed and fruit formation. Specification Point 3.5 - Practical: investigate the conditions needed for seed germination. Specification Point 3.6 - Understand how germinating seeds utilise food reserves until the seedling can carry out photosynthesis. Specification Point 3.7 - Understand that plants can reproduce asexually by natural methods (illustrated by runners) and by artificial methods (illustrated by cuttings). Complete set of Chapter 5 Worksheets are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 8.3 - Understand how geopolitical relationships between countries are important in managing trade, migration and tourism. Complete set of Chapter 9 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.1 - Understand the terms population, community, habitat and ecosystem. Specification Point 4.2 - Practical: investigate the population size of an organism in two different areas using quadrats. Complete set of Chapter 6 Lectures are available.